Fastener cartridge comprising a tissue thickness compensator including openings therein

ABSTRACT

A fastener cartridge assembly. The fastener cartridge assembly can comprise a cartridge body, a tissue thickness compensator releasably secured relative to the cartridge body, and a fastener removably positioned in a staple cavity of the cartridge body. The tissue thickness compensator can comprise a first clearance aperture extending along a first predefined trajectory and a second clearance aperture extending along a second predefined trajectory. The fastener can comprise a first leg aligned with the first clearance aperture and moveable along the first predefined trajectory, a second leg aligned with the second clearance aperture and moveable along the second predefined trajectory. The first and second predefined trajectories can be parallel.

BACKGROUND

The present invention relates to surgical instruments and, in variousembodiments, to surgical cutting and stapling instruments and staplecartridges therefor that are designed to cut and staple tissue.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of this invention, and the manner ofattaining them, will become more apparent and the invention itself willbe better understood by reference to the following description ofembodiments of the invention taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a cross-sectional view of a surgical instrument embodiment;

FIG. 1A is a perspective view of one embodiment of an implantable staplecartridge;

FIGS. 1B-1E illustrate portions of an end effector clamping and staplingtissue with an implantable staple cartridge;

FIG. 2 is a partial cross-sectional side view of another end effectorcoupled to a portion of a surgical instrument with the end effectorsupporting a surgical staple cartridge and with the anvil thereof in anopen position;

FIG. 3 is another partial cross-sectional side view of the end effectorof FIG. 2 in a closed position;

FIG. 4 is another partial cross-sectional side view of the end effectorof FIGS. 2 and 3 as the knife bar is starting to advance through the endeffector;

FIG. 5 is another partial cross-sectional side view of the end effectorof FIGS. 2-4 with the knife bar partially advanced therethrough;

FIG. 6 is a perspective view of an alternative staple cartridgeembodiment installed in a surgical cutting and stapling device;

FIG. 7 is a top view of the surgical staple cartridge and elongatedchannel of the device depicted in FIG. 6;

FIG. 8 is a top view of another surgical staple cartridge embodimentinstalled in an elongated channel of an end effector;

FIG. 9 is a bottom view of an anvil;

FIG. 10 is a partial perspective view of a plurality of staples forminga portion of a staple line;

FIG. 11 is another partial perspective view of the staple line of FIG.10 with the staples thereof after being formed by being contacted by theanvil of the surgical cutting and stapling device;

FIG. 12 is a partial perspective view of alternative staples forming aportion of another staple line;

FIG. 13 is a partial perspective view of alternative staples forming aportion of another staple line;

FIG. 14 is a partial perspective view of alternative staples forming aportion of another staple line embodiment;

FIG. 15 is a cross-sectional view of an end effector supporting a staplecartridge;

FIG. 16 is a cross-sectional view of the elongated channel portion ofthe end effector of FIG. 15 after the implantable staple cartridge bodyportion and staples have been removed therefrom;

FIG. 17 is a cross-sectional view of an end effector supporting anotherstaple cartridge;

FIGS. 18A-18D diagram the deformation of a surgical staple positionedwithin a collapsible staple cartridge body in accordance with at leastone embodiment;

FIG. 19A is a diagram illustrating a staple positioned in a crushablestaple cartridge body;

FIG. 19B is a diagram illustrating the crushable staple cartridge bodyof FIG. 19A being crushed by an anvil;

FIG. 19C is a diagram illustrating the crushable staple cartridge bodyof FIG. 19A being further crushed by the anvil;

FIG. 19D is a diagram illustrating the staple of FIG. 19A in a fullyformed configuration and the crushable staple cartridge of FIG. 19A in afully crushed condition;

FIG. 20 is a diagram depicting a staple positioned against a staplecartridge support surface and illustrating potential relative movementtherebetween;

FIG. 21 is a cross-sectional view of a staple cartridge support surfacecomprising a slot, or trough, configured to stabilize the base of thestaple of FIG. 20;

FIG. 22 is a cross-sectional view of a staple comprising an overmoldedcrown and a slot, or trough, configured to receive a portion of thecrown in accordance with at least one alternative embodiment;

FIG. 23 is a top view of a staple cartridge in accordance with at leastone embodiment comprising staples embedded in a collapsible staplecartridge body;

FIG. 24 is an elevational view of the staple cartridge of FIG. 23;

FIG. 25 is an elevational view of a staple cartridge in accordance withat least one embodiment comprising a protective layer surroundingstaples positioned within a collapsible staple cartridge body;

FIG. 26 is a cross-sectional view of the staple cartridge of FIG. 25taken along line 26-26 in FIG. 25;

FIG. 27 is an elevational view of a staple cartridge in accordance withat least one embodiment comprising staples at least partially extendingoutside of a collapsible staple cartridge body and a protective layersurrounding the staple cartridge body;

FIG. 28 is a cross-sectional view of the staple cartridge of FIG. 27taken along line 28-28 in FIG. 27;

FIG. 29 is a partial break-away view of a staple cartridge in accordancewith at least one embodiment comprising staples at least partiallyembedded in a collapsible staple cartridge body, the staples being atleast partially positioned in a staple cavity void in the staplecartridge body;

FIG. 30 is a cross-sectional view of the staple cartridge of FIG. 29taken along line 30-30 in FIG. 29;

FIG. 31 is a partial break-away view of a staple cartridge in accordancewith at least one embodiment;

FIG. 32 is a partial break-away view of a staple cartridge in accordancewith at least one embodiment comprising staples at least partiallyembedded within a collapsible staple cartridge body and an alignmentmatrix connecting the staples and aligning the staples with respect toeach other;

FIG. 33 is a cross-sectional view of the staple cartridge of FIG. 32taken along line 33-33 in FIG. 32;

FIG. 34 is partial cut-away view of an inner layer of a compressiblestaple cartridge body;

FIG. 35 is a diagram illustrating the inner layer of FIG. 34 compressedbetween a transfer plate and a support plate;

FIG. 36 is a diagram illustrating staples being inserted into thecompressed inner layer of FIG. 35;

FIG. 37 is a diagram of the support plate of FIG. 35 being removed awayfrom the inner layer;

FIG. 38 is a diagram of a subassembly comprising the inner layer of FIG.34 and the staples of FIG. 36 being inserted into an outer layer;

FIG. 39 is a diagram illustrating the outer layer of FIG. 38 beingsealed to form a sealed staple cartridge;

FIG. 40 is a cross-sectional view of the sealed staple cartridge of FIG.39;

FIG. 41 is a cross-sectional view of a staple cartridge and staplecartridge channel in accordance with at least one embodiment;

FIG. 42 is a diagram illustrating a portion of the staple cartridge ofFIG. 41 in a deformed state;

FIG. 43 is an elevational view of an end effector of a surgical staplercomprising an anvil in an open position and a staple cartridgepositioned within a staple cartridge channel;

FIG. 44 is an elevational view of the end effector of FIG. 43illustrating the anvil in a closed position and the staple cartridgecompressed between the anvil and the staple cartridge channel;

FIG. 45 is an elevational view of the end effector of FIG. 43illustrating the staple cartridge of FIG. 43 positioned within thestaple cartridge channel in an alternative manner;

FIG. 46 is a cross-sectional view of an end effector of a surgicalstapler comprising a compressible staple cartridge positioned within astaple cartridge channel and a piece of buttress material attached to ananvil;

FIG. 47 is a cross-sectional view of the end effector of FIG. 46illustrating the anvil in a closed position;

FIG. 48 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising a staple cartridge comprisinga water impermeable layer;

FIG. 49 is a cross-sectional view of another alternative embodiment ofan end effector of a surgical stapler;

FIG. 50 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising a stepped anvil and a staplecartridge comprising a stepped cartridge body;

FIG. 51 is a cross-sectional view of another alternative embodiment ofan end effector of a surgical stapler;

FIG. 52 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising inclined tissue-contactingsurfaces;

FIG. 53 is a cross-sectional view of another alternative embodiment ofan end effector of a surgical stapler comprising inclinedtissue-contacting surfaces;

FIG. 54 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising a support insert configured tosupport a staple cartridge;

FIG. 55 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising a staple cartridge comprisinga plurality of compressible layers;

FIG. 56 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising a staple cartridge comprisinga stepped compressible cartridge body;

FIG. 57 is a cross-sectional view of another alternative embodiment ofan end effector of a surgical stapler comprising a staple cartridgecomprising a stepped compressible cartridge body;

FIG. 58 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising a staple cartridge comprisinga curved tissue-contacting surface;

FIG. 59 is a cross-sectional view of an alternative embodiment of an endeffector of a surgical stapler comprising a staple cartridge having aninclined tissue-contacting surface;

FIG. 60 is a cross-sectional view of a compressible staple cartridgecomprising staples and at least one medicament stored therein;

FIG. 61 is a diagram illustrating the compressible staple cartridge ofFIG. 60 after it has been compressed and the staples contained thereinhave been deformed;

FIG. 62 is a partial cut-away view of a staple cartridge in accordancewith at least one embodiment;

FIG. 63 is a cross-sectional view of the staple cartridge of FIG. 62;

FIG. 64 is a perspective view of an implanted staple cartridge inaccordance with at least one alternative embodiment;

FIG. 65 is a cross-sectional view of the implanted staple cartridge ofFIG. 64;

FIG. 66 is a perspective view of an alternative embodiment of a staplecartridge comprising deformable members extending from an outer layer ofthe staple cartridge;

FIG. 67 is a perspective view of an alternative embodiment of a staplecartridge comprising an outer layer of the staple cartridge beingassembled to an inner layer;

FIG. 68 is a cross-sectional view of an alternative embodiment of astaple cartridge comprising a plurality of staples, a compressiblelayer, and a pledget layer;

FIG. 69 is a perspective view of the pledget layer of FIG. 68;

FIG. 70 is a perspective view of a pledget singulated from the pledgetlayer of FIG. 68 and a staple aligned with a groove in the pledget;

FIG. 71 is a perspective view of two connected pledgets from the pledgetlayer of FIG. 68;

FIG. 72 is a perspective view of a pledget support frame of the pledgetlayer of FIG. 68 being removed from the singulated pledgets;

FIG. 73 is an exploded perspective view of an alternative embodiment ofa compressible staple cartridge comprising staples therein and a systemfor driving the staples against an anvil;

FIG. 73A is a partial cut-away view of an alternative embodiment of thestaple cartridge of FIG. 73;

FIG. 74 is a cross-sectional view of the staple cartridge of FIG. 73;

FIG. 75 is an elevational view of a sled configured to traverse thestaple cartridge of FIG. 73 and move the staples to toward the anvil;

FIG. 76 is a diagram of a staple driver which can be lifted toward theanvil by the sled of FIG. 75;

FIG. 77 is a break-away view of a staple cartridge in accordance with atleast one alternative embodiment comprising staples positioned withinstaple drivers;

FIG. 78 is a cross-sectional view of the staple cartridge of FIG. 77positioned within a staple cartridge channel;

FIG. 79 is a cross-sectional view of the staple cartridge of FIG. 77illustrating an anvil moved into a closed position and staples containedwithin the staple cartridge deformed by the anvil;

FIG. 80 is a cross-sectional view of the staple cartridge of FIG. 77illustrating the staples moved upwardly toward the anvil;

FIG. 81 is a perspective view of an alternative embodiment of a staplecartridge comprising straps connecting the flexible sides of the staplecartridge;

FIG. 82 is a perspective view of a sled and cutting member assembly;

FIG. 83 is a diagram of the sled and cutting member assembly of FIG. 82being used to lift the staples of the staple cartridge of FIG. 77;

FIG. 84 is a diagram illustrating a sled configured to engage and liftstaples toward an anvil and a lock-out system configured to selectivelypermit the sled to move distally;

FIGS. 85A-85C illustrate the progression of a staple being inserted intoa staple crown;

FIG. 86 is a cross-sectional view of a staple cartridge comprising asupport pan or retainer;

FIG. 87 is a partial cross-sectional view of a compressible staplecartridge in accordance with at least one alternative embodiment;

FIG. 88 is a diagram illustrating the staple cartridge of FIG. 87 in animplanted condition;

FIG. 89 is a partial cut-away view of a compressible staple cartridge inaccordance with at least one alternative embodiment;

FIG. 90 is a partial cross-sectional view of the staple cartridge ofFIG. 89;

FIG. 91 is a diagram illustrating the staple cartridge of FIG. 89 in animplanted condition;

FIG. 92 is a partial cross-sectional view of a crushable staplecartridge in accordance with at least one alternative embodiment;

FIG. 93 is a partial cut-away view of a collapsible staple cartridge inaccordance with at least one embodiment comprising a plurality ofcollapsible elements;

FIG. 94 is a perspective view of a collapsible element of FIG. 93 in anuncollapsed state;

FIG. 95 is a perspective view of the collapsible element of FIG. 94 in acollapsed state;

FIG. 96A is a partial cross-sectional view of an end effector of asurgical stapling instrument comprising a jaw, a staple cartridgechannel positioned opposite the jaw, and a staple cartridge positionedwithin the staple cartridge channel, wherein the jaw comprises aretention matrix attached thereto;

FIG. 96B is a partial cross-sectional view of the end effector of FIG.96A illustrating the jaw being moved toward the staple cartridgechannel, the staple cartridge being compressed by the anvil and theretention matrix, and a staple at least partially extending throughtissue positioned intermediate the retention matrix and the staplecartridge;

FIG. 96C is a partial cross-sectional view of the end effector of FIG.96A illustrating the jaw in a final position and the retention matrixengaged with the staple of FIG. 96B;

FIG. 96D is a partial cross-sectional view of the end effector of FIG.96A illustrating the jaw and the staple cartridge channel being movedaway from the implanted staple cartridge and retention matrix;

FIG. 97 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisinga plurality of retention members configured to engage a fastener legextending therethrough;

FIG. 98 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisingsix retention members;

FIG. 99 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisingeight retention members;

FIG. 100 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisinga plurality of retention members configured to engage a fastener legextending therethrough;

FIG. 101 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisingsix retention members;

FIG. 102 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisingeight retention members;

FIG. 103 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisinga plurality of retention members that have been stamped from a sheet ofmetal;

FIG. 104 is a perspective view of a retention aperture of a retentionmatrix in accordance with at least one alternative embodiment comprisinga plurality of apertures extending around the perimeter of the retentionaperture;

FIG. 105 is a top view of a retention aperture of a retention matrix inaccordance with at least one alternative embodiment;

FIG. 106 is a top view of a retention aperture of a retention matrix inaccordance with at least one alternative embodiment;

FIG. 107 is a top view of a retention aperture of a retention matrix inaccordance with at least one alternative embodiment;

FIG. 108 is a top view of a retention aperture of a retention matrix inaccordance with at least one alternative embodiment;

FIG. 109 is a top view of a retention aperture of a retention matrix inaccordance with at least one alternative embodiment;

FIG. 110 is a top view of a retention aperture of a retention matrixcomprising a retention tab extending into the retention aperture inaccordance with at least one embodiment;

FIG. 111 is a top view of a retention aperture of a retention matrixcomprising a retention tab extending into the retention aperture inaccordance with at least one alternative embodiment;

FIG. 112 is a perspective view of a fastening system comprising aplurality of staples, a retention matrix engaged with the staples, andan alignment matrix configured to align the staples;

FIG. 113 is a perspective view of the retention matrix of FIG. 112;

FIG. 114 is a perspective view of the alignment matrix of FIG. 112;

FIG. 115 is a partial top view of the retention matrix of FIG. 112engaged with the staples of FIG. 112;

FIG. 116 is a partial bottom view of the retention matrix of FIG. 112engaged with the staples of FIG. 112;

FIG. 117 is a partial elevational view of the fastening system of FIG.112;

FIG. 118 is a partial perspective view of the fastening system of FIG.112;

FIG. 119 is a partial cross-sectional view of the retention matrix ofFIG. 112 engaged with the staples of FIG. 112;

FIG. 120 is a partial cross-sectional view of the fastening system ofFIG. 112;

FIG. 121 is a perspective view of the fastening system of FIG. 112further comprising protective caps assembled to the legs of the staples;

FIG. 122 is a bottom perspective view of the fastening systemarrangement of FIG. 121;

FIG. 123 is a partial perspective view of the fastening systemarrangement of FIG. 121;

FIG. 124 is a partial cross-sectional view of the fastening systemarrangement of FIG. 121;

FIG. 125 is an elevational view of an end effector in accordance with atleast one embodiment comprising a jaw in an open position, a retentionmatrix and a plurality of protective caps positioned in the jaw, and astaple cartridge positioned in a staple cartridge channel;

FIG. 126 is an elevational view of the end effector of FIG. 125 in aclosed position;

FIG. 127 is an elevational view of the end effector of FIG. 125 in afired position;

FIG. 128 is an elevational view of the retention matrix and protectivecaps of FIG. 125 assembled to the staple cartridge of FIG. 125;

FIG. 129 is a detail view of the arrangement of FIG. 128;

FIG. 130 is an elevational view of the end effector of FIG. 125illustrating the jaw in an open position with thinner tissue positionedbetween the retention matrix and the staple cartridge;

FIG. 131 is an elevational view of the end effector of FIG. 125illustrating the jaw in a closed position against the thinner tissue ofFIG. 130;

FIG. 132 is an elevational view of the end effector of FIG. 125illustrating the jaw in a fired position to capture the thinner tissueof FIG. 130 between the retention matrix and the staple cartridge;

FIG. 133 is an elevational view of the retention matrix and theprotective caps of FIG. 125 assembled to the staple cartridge of FIG.125 with the thin tissue of FIG. 130 positioned therebetween;

FIG. 134 is a detail view of the arrangement of FIG. 133;

FIG. 135 is a cross-sectional view of a protective cap positioned on thetip of a staple leg in accordance with at least one alternativeembodiment;

FIG. 136 is a perspective view of a plurality of protective capsembedded within a sheet of material;

FIG. 137 is a perspective view of a jaw comprising a plurality ofrecesses configured to receive a plurality of protective caps therein;

FIG. 138 is a detail view of a portion of a jaw comprising a sheetcovering the protective caps positioned within the jaw of FIG. 137;

FIG. 139 is a cross-sectional view of a protective cap positioned on atip of a staple leg in accordance with at least one alternativeembodiment wherein the protective cap comprises an interior formingsurface;

FIG. 140 is another cross-sectional view of the protective cap of FIG.139 illustrating the staple leg being deformed against the formingsurface;

FIG. 141 is a top view of an alternative embodiment of a retentionmatrix comprising a plurality of connected matrix elements;

FIG. 142 is a top view of an alternative embodiment of a retentionmatrix comprising a plurality of connected matrix elements;

FIG. 143 is a top view of an alternative embodiment of a retentionmatrix comprising a plurality of connected matrix elements;

FIG. 144 is a top view of an alternative embodiment of an array ofretention matrices comprising a plurality of connected matrix elements;

FIG. 145 is a top view of an alternative embodiment of a retentionmatrix comprising a plurality of connected matrix elements;

FIG. 146 is a partial exploded view of a jaw comprising a retentionmatrix including a compressible cover;

FIG. 147 is a detail view of the retention matrix of FIG. 146;

FIG. 148 is a partial cross-sectional view of a fastening systemcomprising a retention matrix including a compressible layer and aplurality of cells encapsulating one or more medicaments;

FIG. 149 is a diagram illustrating staple legs which have pierced thecells of FIG. 148 as they are being engaged with the retention matrix;

FIG. 150 is a partial cross-sectional view of a fastening systemcomprising a retention matrix including a compressible layer;

FIG. 151 is an elevational view of a fastener cartridge insertionassembly comprising a holder, a first fastener cartridge, and a secondfastener cartridge;

FIG. 152 is an elevational view of an end effector of a surgical staplercomprising a first jaw and a second jaw, the second jaw beingillustrated in an open configuration;

FIG. 153 is an elevational view of the end effector of FIG. 152illustrating the second jaw in a closed configuration and the fastenercartridge insertion assembly of FIG. 151 being used to load the firstjaw with the first cartridge and the second jaw with the secondcartridge;

FIG. 154 is an elevational view of the loaded end effector of FIG. 153illustrating the cartridge insertion assembly removed from the endeffector, the second jaw in an open configuration once again, and tissuepositioned intermediate the first jaw and the second jaw;

FIG. 155 is an elevational view of the loaded end effector of FIG. 154in a fired configuration;

FIG. 156 is an elevational view of the first cartridge and the secondcartridge in an implanted condition;

FIG. 157 is an elevational view of the end effector of FIG. 152illustrating a portion of the first cartridge still engaged with thefirst jaw in accordance with at least one embodiment;

FIG. 158 is an elevational view of an alternative embodiment of afastener cartridge insertion assembly comprising a holder, a firstfastener cartridge, and a second fastener cartridge;

FIG. 159 is an elevational view of the fastener cartridge insertionassembly of FIG. 158 being used to load a first jaw of an end effectorwith the first cartridge and a second jaw with the second cartridge;

FIG. 160 is a cross-sectional view of the loaded end effector of FIG.159;

FIG. 161 is a perspective view of a surgical stapler comprising a bottomjaw and a top jaw in accordance with at least one embodiment illustratedwith portions of the surgical stapler removed;

FIG. 162 is a perspective view of the surgical stapler of FIG. 161 withthe top jaw removed;

FIG. 163 is a perspective view of a slidable anvil system of the top jawof the surgical stapler of FIG. 161 comprising a first slidable anviland a second slidable anvil;

FIG. 164 is an end view of the slidable anvil system of FIG. 163;

FIG. 165 is a top view of the slidable anvil system of FIG. 163;

FIG. 166 is a diagram illustrating the slidable anvil system of FIG. 163in an unfired condition;

FIG. 167 is a diagram illustrating the first slidable anvil of theslidable anvil system of FIG. 163 in an unfired position and staplespositioned within the bottom jaw in an undeployed position;

FIG. 168 is a diagram illustrating the staples in the bottom jaw in adeployed configuration and the first slidable anvil of FIG. 167 beingpulled proximally to deform a first group of staple legs of the staples;

FIG. 169 is a diagram illustrating the first group of staples of FIG.168 deformed to a fully deformed state;

FIG. 170 is a diagram illustrating the second slidable anvil of theslidable anvil system of FIG. 163 being pushed distally to deform asecond group of staple legs;

FIG. 171 is a partial perspective view of an anvil comprising aplurality of forming pockets in at least one embodiment;

FIG. 172 is a cross-sectional end view of the anvil of FIG. 171;

FIG. 173 is a diagram illustrating a first step in manufacturing theforming pockets of FIG. 171;

FIG. 174 is a diagram illustrating a second step in manufacturing theforming pockets of FIG. 171;

FIG. 175 is a top view of the forming pocket arrangement of the anvil ofFIG. 171;

FIG. 176 is a diagram illustrating a first step of a manufacturingprocess for producing an anvil;

FIG. 177 is a diagram illustrating a second step in the manufacturingprocess of FIG. 176;

FIG. 178 is a diagram illustrating a third step in the manufacturingprocess of FIG. 176;

FIG. 179 is a left front perspective view of a surgical stapling andsevering instrument with a handle portion including a link triggeredautomatic retraction and a ratcheting manual retraction mechanism;

FIG. 180 is a right aft perspective view of the surgical stapling andsevering instrument of FIG. 179 with a portion of an elongate shaft cutaway and a right half shell of a handle housing removed to expose anautomatic end-of-firing travel retraction mechanism and a manual firingretraction mechanism;

FIG. 181 is a right aft perspective disassembled view of the handleportion and an elongate shaft of the surgical stapling and severinginstrument of FIG. 179;

FIG. 182 is a right aft perspective view of the surgical stapling andsevering instrument of FIG. 31 with a right half shell and outerportions of the implement portion removed to expose the closure andfiring mechanisms in an initial state;

FIG. 183 is a right side view in elevation of the partially disassembledsurgical stapling and severing instrument of FIG. 182;

FIG. 184 is a right aft perspective view of the partially disassembledsurgical stapling and severing instrument of FIG. 182 with a closuremechanism closed and clamped and the side pawl firing mechanismcompleting a first stroke and with a manual retraction mechanism removedto expose a distal link of the linked rack that triggers automaticretraction of the firing mechanism;

FIG. 185 is a right aft perspective view of the partially disassembledsurgical stapling and severing instrument of FIG. 183 with the side pawlfiring mechanism disengaged and the distal link approaching automaticretraction;

FIG. 186 is left side view in elevation of the partially disassembledsurgical stapling and severing instrument of FIG. 183 in an initialstate of end effector open and anti-backup mechanism engaged;

FIG. 187 is a left side detail view of the right half shell and ananti-backup release lever of the handle portion of FIG. 186;

FIG. 188 is a left side detail view in elevation of the disassembledsurgical stapling and severing instrument of FIG. 179 with the closuretrigger clamped, the firing trigger performing a final stroke and thedistal link positioned to trip automatic retraction;

FIG. 189 is a left side detail in elevation of the disassembled surgicalstapling and severing instrument of FIG. 188 immediately after thedistal link has actuated and locked forward the anti-backup releaselever, allowing the linked rack to retract;

FIG. 190 is a right disassembled perspective view of the idler and aftgears and manual retraction lever and ratcheting pawl of a manualretraction mechanism of the surgical stapling and severing instrument ofFIG. 179;

FIG. 191 is a right perspective view of the manual retraction mechanismof FIG. 190 with the manual retraction lever partially cut away toexpose a smaller diameter ratchet gear on the aft gear engaging theratcheting pawl;

FIG. 192 is a partially disassembled left side view in elevation of asurgical stapling and severing instrument of FIG. 179 with theanti-backup mechanism engaged to a fully fired linked rack that isdisconnected from a combination tension/compression spring prior toactuation of the manual retraction lever of FIG. 190;

FIG. 193 is a partially disassembled left side view in elevation of thesurgical stapling and severing instrument of FIG. 192 with hiddenportions of the anti-backup release lever, aft gear, and manual firingrelease lever shown in phantom;

FIG. 194 is a partially disassembled left side view in elevation of thesurgical stapling and severing instrument of FIG. 193 after actuation ofthe manual firing release lever has manually retracted the link rack;

FIG. 195 is a partially disassembled left side view in elevation of thesurgical stapling and severing instrument of FIG. 194 with the linkedrack omitted depicting the manual firing release lever disengaging theanti-backup mechanism;

FIG. 196 is a left side detail view of an alternative anti-backuprelease lever and handle housing for the surgical stapling and severinginstrument of FIG. 179;

FIG. 197 is a left perspective disassembled view of the alternativeanti-backup release lever, aft gear axle, and automatic retraction camwheel of FIG. 196;

FIG. 198 is a right side view in elevation of the alternativeanti-backup release mechanism of FIG. 196 with the linked rack in aretracted position and the anti-backup release lever proximallypositioned with the anti-backup plate engaged to the firing rod;

FIG. 198A is a right detail side view in elevation of the aft gear,automatic retraction cam wheel and distal-most link of FIG. 198;

FIG. 199 is a right side view in elevation of the anti-backup releasemechanism of FIG. 198 after a first firing stroke;

FIG. 199A is a right detail side view in elevation of the aft gear,automatic retraction cam wheel and a second link of FIG. 199;

FIG. 200 is a right side view in elevation of the anti-backup releasemechanism of FIG. 199 after a second firing stroke;

FIG. 200A is a right detail side view in elevation of the aft gear,automatic retraction cam wheel and third link of FIG. 200;

FIG. 201 is a right detail side view in elevation of the anti-backuprelease mechanism of FIG. 200 after a third firing and final stroke;

FIG. 201A is a right detail side view in elevation of the aft gear,automatic retraction cam wheel and proximal-most fourth link of FIG.201;

FIG. 202 is a right side view in elevation of the automatic releasemechanism of FIG. 201 after a further firing stroke causes the automaticretraction cam wheel to distally slide and lock the anti-backup releaselever, disengaging the anti-backup mechanism;

FIG. 203 is a left, front perspective view of an open staple applyingassembly with a right half portion of a replaceable staple cartridgeincluded in a staple channel;

FIG. 204 is an exploded perspective view of the staple applying assemblyof FIG. 203 with a complete replaceable staple cartridge and annonarticulating shaft configuration;

FIG. 205 is a perspective view of a two-piece knife and firing bar(“E-beam”) of the staple applying assembly of FIG. 203;

FIG. 206 is a perspective view of a wedge sled of a staple cartridge ofa staple applying assembly;

FIG. 207 is a left side view in elevation taken in longitudinal crosssection along a centerline line 207-207 of the staple applying assemblyof FIG. 203;

FIG. 208 is a perspective view of the open staple applying assembly ofFIG. 203 without the replaceable staple cartridge, a portion of thestaple channel proximate to a middle pin of two-piece knife and firingbar, and without a distal portion of a staple channel;

FIG. 209 is a front view in elevation taken in cross section along line209-209 of the staple applying assembly of FIG. 203 depicting internalstaple drivers of the staple cartridge and portions of the two-pieceknife and firing bar;

FIG. 210 is a left side view in elevation taken generally along thelongitudinal axis of line 207-207 of a closed staple applying assemblyof FIG. 203 to include center contact points between the two-piece knifeand wedge sled but also laterally offset to show staples and stapledrivers within the staple cartridge;

FIG. 211 is a left side detail view in elevation of the staple applyingassembly of FIG. 210 with the two-piece knife retracted slightly more astypical for staple cartridge replacement;

FIG. 212 is a left side detail view in elevation of the staple applyingassembly of FIG. 211 with the two-piece knife beginning to fire,corresponding to the configuration depicted in FIG. 210;

FIG. 213 is a left side cross-sectional view in elevation of the closedstaple applying assembly of FIG. 210 after the two-piece knife andfiring bar has distally fired;

FIG. 214 is a left side cross-sectional view in elevation of the closedstaple applying assembly of FIG. 213 after firing of the staplecartridge and retraction of the two-piece knife;

FIG. 215 is a left side cross-sectional detail view in elevation of thestaple applying assembly of FIG. 214 with the two-piece knife allowed todrop into a lockout position;

FIG. 216 is a perspective view of a staple cartridge comprising a rigidsupport portion and a compressible tissue thickness compensator for usewith a surgical stapling instrument in accordance with at least oneembodiment of the invention;

FIG. 217 is a partially exploded view of the staple cartridge of FIG.216;

FIG. 218 is a fully exploded view of the staple cartridge of FIG. 216;

FIG. 219 is another exploded view of the staple cartridge of FIG. 216without a warp covering the tissue thickness compensator;

FIG. 220 is a perspective view of a cartridge body, or support portion,of the staple cartridge of FIG. 216;

FIG. 221 is a top perspective view of a sled movable within the staplecartridge of FIG. 216 to deploy staples from the staple cartridge;

FIG. 222 is a bottom perspective view of the sled of FIG. 221;

FIG. 223 is an elevational view of the sled of FIG. 221;

FIG. 224 is a top perspective view of a driver configured to support oneor more staples and to be lifted upwardly by the sled of FIG. 221 toeject the staples from the staple cartridge;

FIG. 225 is a bottom perspective view of the driver of FIG. 224;

FIG. 226 is a wrap configured to at least partially surround acompressible tissue thickness compensator of a staple cartridge;

FIG. 227 is a partial cut away view of a staple cartridge comprising arigid support portion and a compressible tissue thickness compensatorillustrated with staples being moved from an unfired position to a firedposition during a first sequence;

FIG. 228 is an elevational view of the staple cartridge of FIG. 227;

FIG. 229 is a detail elevational view of the staple cartridge of FIG.227;

FIG. 230 is a cross-sectional end view of the staple cartridge of FIG.227;

FIG. 231 is a bottom view of the staple cartridge of FIG. 227;

FIG. 232 is a detail bottom view of the staple cartridge of FIG. 227;

FIG. 233 is a longitudinal cross-sectional view of an anvil in a closedposition and a staple cartridge comprising a rigid support portion and acompressible tissue thickness compensator illustrated with staples beingmoved from an unfired position to a fired position during a firstsequence;

FIG. 234 is another cross-sectional view of the anvil and the staplecartridge of FIG. 233 illustrating the anvil in an open position afterthe firing sequence has been completed;

FIG. 235 is a partial detail view of the staple cartridge of FIG. 233illustrating the staples in an unfired position;

FIG. 236 is a cross-sectional elevational view of a staple cartridgecomprising a rigid support portion and a compressible tissue thicknesscompensator illustrating the staples in an unfired position;

FIG. 237 is a detail view of the staple cartridge of FIG. 236;

FIG. 238 is an elevational view of an anvil in an open position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition;

FIG. 239 is an elevational view of an anvil in a closed position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition and tissue captured between the anvil and the tissue thicknesscompensator;

FIG. 240 is a detail view of the anvil and staple cartridge of FIG. 239;

FIG. 241 is an elevational view of an anvil in a closed position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition illustrating thicker tissue positioned between the anvil andthe staple cartridge;

FIG. 242 is a detail view of the anvil and staple cartridge of FIG. 241;

FIG. 243 is an elevational view of the anvil and staple cartridge ofFIG. 241 illustrating tissue having different thicknesses positionedbetween the anvil and the staple cartridge;

FIG. 244 is a detail view of the anvil and staple cartridge of FIG. 241as illustrated in FIG. 243;

FIG. 245 is a diagram illustrating a tissue thickness compensator whichis compensating for different tissue thickness captured within differentstaples;

FIG. 246 is a diagram illustrating a tissue thickness compensatorapplying a compressive pressure to one or more vessels that have beentransected by a staple line;

FIG. 247 is a diagram illustrating a circumstance wherein one or morestaples have been improperly formed;

FIG. 248 is a diagram illustrating a tissue thickness compensator whichcould compensate for improperly formed staples;

FIG. 249 is a diagram illustrating a tissue thickness compensatorpositioned in a region of tissue in which multiple staples lines haveintersected;

FIG. 250 is a diagram illustrating tissue captured within a staple;

FIG. 251 is a diagram illustrating tissue and a tissue thicknesscompensator captured within a staple;

FIG. 252 is a diagram illustrating tissue captured within a staple;

FIG. 253 is a diagram illustrating thick tissue and a tissue thicknesscompensator captured within a staple;

FIG. 254 is a diagram illustrating thin tissue and a tissue thicknesscompensator captured within a staple;

FIG. 255 is a diagram illustrating tissue having an intermediatethickness and a tissue thickness compensator captured within a staple;

FIG. 256 is a diagram illustrating tissue having another intermediatethickness and a tissue thickness compensator captured within a staple;

FIG. 257 is a diagram illustrating thick tissue and a tissue thicknesscompensator captured within a staple;

FIG. 258 is a partial cross-sectional view of an end effector of asurgical stapling instrument illustrating a firing bar and staple-firingsled in a retracted, unfired position;

FIG. 259 is another partial cross-sectional view of the end effector ofFIG. 258 illustrating the firing bar and the staple-firing sled in apartially advanced position;

FIG. 260 is a cross-sectional view of the end effector of FIG. 258illustrating the firing bar in a fully advanced, or fired, position;

FIG. 261 is a cross-sectional view of the end effector of FIG. 258illustrating the firing bar in a retracted position after being firedand the staple-firing sled left in its fully fired position;

FIG. 262 is a detail view of the firing bar in the retracted position ofFIG. 261;

FIG. 263 is a partial cross-sectional view of an end effector of asurgical stapling instrument including a staple cartridge comprising atissue thickness compensator and staples at least partially positionedtherein;

FIG. 264 is another partial cross-sectional view of the end effector ofFIG. 263 illustrating the staples at least partially moved and/orrotated relative to an anvil positioned opposite the staple cartridge;

FIG. 265 is a partial cross-sectional view of an end effector of asurgical stapling instrument in accordance with at least one embodiment;

FIG. 266 is a partial cross-sectional view of an end effector inaccordance with at least one alternative embodiment;

FIG. 267 is a partial cross-sectional view of an end effector inaccordance with another alternative embodiment;

FIG. 268 is a perspective view of an end effector of a surgical staplinginstrument in accordance with at least one embodiment;

FIG. 269 is a partial cross-sectional view of the end effector of FIG.268 illustrated in a flexed condition;

FIG. 270 is a partial cross-sectional view of the end effector of FIG.269 in a released condition;

FIG. 271 is a perspective view of an end effector comprising a tissuethickness compensator sock;

FIG. 272 is a rear perspective of the tissue thickness compensator sockin FIG. 271;

FIG. 273 is a perspective view of an end effector comprising a pluralityof rails extending from a support portion and a tissue thicknesscompensator having a longitudinal cavity defined therein;

FIG. 274 is a perspective view of the tissue thickness compensator ofFIG. 273;

FIG. 275 is a perspective view of an end effector comprising a pluralityof teeth extending from a support portion and a tissue thicknesscompensator engaged therewith;

FIG. 276 is a perspective view of an anvil comprising a pocket array inaccordance with at least one embodiment;

FIG. 277 is a partial detail view of the anvil of FIG. 276;

FIG. 278 is a partial longitudinal cross-sectional view of the anvil ofFIG. 276;

FIG. 279 is a transverse cross-sectional view of the anvil of FIG. 276;

FIG. 280 is an elevational view of a fired staple comprising asubstantially B-shaped configuration;

FIG. 281 is an elevational view of a fired staple comprising one legdeformed inwardly and one leg deformed outwardly;

FIG. 282 is an elevational view of a fired staple comprising both legsformed outwardly;

FIG. 283 is a partial perspective view of a support portion of a staplecartridge comprising detachable and/or displaceable staple leg guides;

FIG. 284 is a partial cross-sectional view of the staple cartridge ofFIG. 283 illustrating staples being deployed from the staple cartridge;

FIG. 285 is a detail view of the cross-sectional view of FIG. 284 afterthe staple cartridge has been fired;

FIG. 286 is an exploded view of a staple cartridge including a tissuethickness compensator comprising voids defined therein;

FIG. 287 is a diagram illustrating the tissue thickness compensator ofFIG. 286 implanted against tissue;

FIG. 288 is another diagram illustrating the tissue thicknesscompensator of FIG. 286 implanted against tissue;

FIG. 289 is a cross-sectional perspective view of a staple cartridgecomprising lateral retention members extending from a support portionthereof configured to hold a tissue thickness compensator in position;

FIG. 290 is a cross-sectional view of the staple cartridge of FIG. 289being utilized to staple tissue;

FIG. 291 is another cross-sectional view of the staple cartridge of FIG.289 illustrating the support portion being moved away from the implantedtissue thickness compensator;

FIG. 292 is a cross-sectional perspective view of a staple cartridgecomprising lateral retention members configured to hold a tissuethickness compensator to a support portion;

FIG. 293 is a cross-sectional view of the staple cartridge of FIG. 292being utilized to staple tissue;

FIG. 294 is another cross-sectional view of the staple cartridge of FIG.292 illustrating the support portion being moved away from the implantedtissue thickness compensator;

FIG. 295 is a cross-sectional detail view of a retainer holding a tissuethickness compensator to a support portion of a staple cartridge inaccordance with at least one embodiment;

FIG. 296 is partial cut-away view of a staple cartridge comprisingstaple drivers having different heights in accordance with at least oneembodiment;

FIG. 296A is a diagram illustrating the staple drivers of FIG. 296 andstaples having different unfired heights supported thereon;

FIG. 297 is a diagram illustrating a tissue thickness compensatorcomprising a varying thickness, staple drivers having different heights,and staples having different unformed heights;

FIG. 298 is a diagram illustrating the staples and the tissue thicknesscompensator of FIG. 297 implanted to tissue;

FIG. 299 is a partial cross-sectional view of a staple cartridgecomprising a tissue thickness compensator comprising a varying thicknessin accordance with at least one embodiment;

FIG. 300 is a cross-sectional view of an end effector of a surgicalstapling instrument in an open configuration;

FIG. 301 is cross-sectional view of the end effector of FIG. 300illustrated in a partially-fired configuration;

FIG. 302 is a cross-sectional view of the end effector of FIG. 300illustrated in a re-opened configuration;

FIG. 303 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising staple drivers having different heightsand a contoured deck surface in accordance with at least one embodiment;

FIG. 304 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising staple drivers having different heightsand a stepped deck surface in accordance with at least one embodiment;

FIG. 305 is a perspective view of a staple cartridge being loaded intoan effector of a surgical stapling instrument utilizing a staplecartridge applicator;

FIG. 306 is a bottom perspective view of the staple cartridge applicatorof FIG. 305;

FIG. 307 is a side view of the staple cartridge applicator of FIG. 305assembled to a staple cartridge;

FIG. 308 is a cross-sectional view of the assembly of FIG. 307;

FIG. 309 is a perspective view of a staple cartridge applicator assemblyfurther including an upper tissue thickness compensator positioned onthe top surface of the staple cartridge applicator in accordance with atleast one embodiment;

FIG. 310 is an exploded view of the upper tissue thickness compensatorand the staple cartridge applicator of FIG. 309;

FIG. 310A is an exploded view of a staple cartridge applicator assemblycomprising a pull member configured to detach an upper tissue thicknesscompensator adhered to the staple cartridge applicator;

FIG. 311 is a partial exploded view of a staple cartridge applicatorassembly in accordance with at least one alternative embodiment;

FIG. 312 is a perspective view of a staple cartridge applicator assemblycomprising an upper tissue thickness compensator including a pluralityof retention features extending therefrom and a staple cartridgecomprising a lower tissue thickness compensator;

FIG. 313 is an elevational view of the staple cartridge applicatorassembly of FIG. 312 positioned within a staple cartridge channel and ananvil being closed onto the staple cartridge applicator assembly;

FIG. 314 is an elevational view of the anvil of FIG. 313 in a re-openedposition and the staple cartridge applicator of FIG. 312 being removedfrom the end effector;

FIG. 314A is a cross-sectional view of tissue positioned intermediatethe upper tissue thickness compensator and the lower tissue thicknesscompensator of FIG. 312;

FIG. 314B is a cross-sectional view illustrating the upper tissuethickness compensator and the lower tissue thickness compensator stapledto the tissue and severed by a cutting member;

FIG. 315 is a diagram illustrating a tissue thickness compensator beinginserted into an anvil in accordance with at least one embodiment;

FIG. 316 is a cross-sectional view of the tissue thickness compensatorof FIG. 315;

FIG. 317 is an exploded view of a tissue thickness compensator and ananvil in accordance with at least one alternative embodiment;

FIG. 318 is a perspective view of staple cartridge applicator assemblycomprising an upper tissue thickness compensator configured to beattached to an anvil in accordance with at least one embodiment;

FIG. 319 is an elevational view of the staple cartridge applicatorassembly of FIG. 318 positioned within a staple cartridge channel and ananvil being moved toward the upper tissue thickness compensator;

FIG. 320 illustrates the staple cartridge applicator of FIG. 318 beingremoved from the end effector after the upper tissue thicknesscompensator has been engaged with the anvil;

FIG. 321 is a cross-sectional end view of the anvil being moved towardthe upper tissue thickness compensator of FIG. 318;

FIG. 322 is a cross-sectional end view of the anvil engaged with theupper tissue thickness compensator;

FIG. 323 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising a staple cartridge including asegmentable tissue thickness compensator attached to a support portionof the staple cartridge by a plurality of fasteners;

FIG. 324 is a cross-sectional view of the end effector of FIG. 323illustrating a firing member in a partially-fired position;

FIG. 325 is a cross-sectional view of the end effector of FIG. 323illustrating the support portion being moved away from thepartially-implanted tissue thickness compensator;

FIG. 326 is a partial perspective view of the support portion of FIG.323;

FIG. 327 is a perspective view of a staple-deploying sled in accordancewith at least one embodiment;

FIG. 328 is an elevational view of the sled of FIG. 327;

FIG. 329 is a perspective view of an end effector of a surgical staplinginstrument comprising a staple cartridge including a tissue thicknesscompensator and a plurality of staple guides positioned on the tissuethickness compensator;

FIG. 330 is a partial cross-sectional view of the tissue thicknesscompensator and the staple guides of FIG. 329 in an unfiredconfiguration;

FIG. 331 is a partial cross-sectional view of the tissue thicknesscompensator and the staple guides of FIG. 329 in a fired configuration;

FIG. 332 is a cross-sectional view of a staple cartridge comprising atissue thickness compensator and a support portion in accordance with atleast one embodiment;

FIG. 333 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired position;

FIG. 334 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 335 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 336 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 337 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 338 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 339 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 340 is a detail view of a region surrounding a tip of the staple ofFIG. 339;

FIG. 341 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 342 is a detail view of a region surrounding a tip of the staple ofFIG. 341;

FIG. 343 is a partial cross-sectional view of a tissue thicknesscompensator, a staple guide layer, and a staple in an unfired positionin accordance with at least one alternative embodiment;

FIG. 344 is a perspective view of a staple guide layer and a pluralityof staples in an unfired position in accordance with at least onealternative embodiment;

FIG. 345 is an end view of a tissue thickness compensator configured tobe used with a circular surgical stapler;

FIG. 346 is a perspective view of the tissue thickness compensator andthe circular surgical stapler of FIG. 345;

FIG. 347 is an end view of a tissue thickness compensator configured tobe used with a circular surgical stapler in accordance with at least onealternative embodiment;

FIG. 348 is a perspective view of the tissue thickness compensator andthe circular surgical stapler of FIG. 347;

FIG. 349 is an end view of a tissue thickness compensator configured tobe used with a circular surgical stapler;

FIG. 350 is an end view of the tissue thickness compensator of FIG. 349in a partially expanded configuration;

FIG. 351 is an elevational view of a surgical stapling instrumentcomprising a staple cartridge in accordance with at least oneembodiment;

FIG. 352 is an end view of the surgical stapling instrument of FIG. 351positioned relative to tissue;

FIG. 353 is an end view of the surgical stapling instrument of FIG. 351further comprising a tissue thickness compensator positioned between thestaple cartridge and the tissue;

FIG. 354 is a partial perspective view of staples deployed into tissuefrom the surgical stapling instrument of FIG. 351 without a tissuethickness compensator;

FIG. 355 is a partial perspective view of staples deployed into tissuefrom the surgical stapling instrument of FIG. 351 with a tissuethickness compensator;

FIG. 356 is a partial cross-sectional view of the end effector of thesurgical stapling instrument of FIG. 351 comprising an anvil plate in afirst position;

FIG. 357 is a partial cross-sectional view of the end effector of thesurgical stapling instrument of FIG. 351 illustrating the anvil plate ofFIG. 356 in a second position;

FIG. 358 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising a staple cartridge including a gapsetting element;

FIG. 359 is a perspective view illustrating a firing member cutting thegap setting element of FIG. 358 at the end of firing stroke of thefiring member;

FIG. 360 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising a staple cartridge including a flexiblenose;

FIG. 361 is a cross-sectional view of the end effector of FIG. 360illustrating the nose in a flexed configuration;

FIG. 362 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising a staple cartridge including a slidableportion;

FIG. 363 is a cross-sectional view of the end effector of FIG. 362illustrating the slidable portion slid distally;

FIG. 364 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising a support portion comprising an inclineddeck surface and a tissue thickness compensator comprising a varyingthickness;

FIG. 365 is a cross-sectional view of an end effector of a surgicalstapling instrument comprising a support portion comprising an inclineddeck surface and a tissue thickness compensator comprising a uniformthickness;

FIG. 366 is a perspective view of a staple cartridge comprising a tissuethickness compensator having a varying thickness;

FIG. 367 is an end view of the staple cartridge of FIG. 366;

FIG. 368 is a cross-sectional perspective view of a tissue thicknesscompensator comprising longitudinal layers;

FIG. 369 is a cross-sectional perspective view of a tissue thicknesscompensator comprising a plurality of layers in accordance with at leastone alternative embodiment;

FIG. 370 is a perspective view of a disposable loading unit comprisingretention members configured to releasably hold a tissue thicknesscompensator thereto;

FIG. 371 is a perspective view of a tissue thickness compensatorincluding retention members configured to releasably hold the tissuethickness compensator to a disposable loading unit;

FIG. 372 is a perspective view of the tissue thickness compensator ofFIG. 371 attached to a disposable loading unit;

FIG. 373 is an end view of the disposable loading unit of FIG. 372;

FIG. 374 is a perspective view of a tissue thickness compensatorincluding retention members configured to releasably hold the tissuethickness compensator to a disposable loading unit;

FIG. 375 is a perspective view of the tissue thickness compensator ofFIG. 374 attached to a disposable loading unit;

FIG. 376 is an end view of the disposable loading unit of FIG. 375;

FIG. 377 is a perspective view of a tissue thickness compensatorincluding a retention member configured to releasably hold the tissuethickness compensator to a disposable loading unit;

FIG. 378 is a perspective view of the tissue thickness compensator ofFIG. 377 attached to a disposable loading unit;

FIG. 379 is a perspective view of a tissue thickness compensatorapplicator positioned within an effector of a disposable loading unit;

FIG. 380 is a top perspective view of the tissue thickness compensatorapplicator of FIG. 379;

FIG. 381 is a bottom perspective view of the tissue thicknesscompensator applicator of FIG. 379;

FIG. 382 is a perspective view of a tissue thickness compensatorapplicator positioned within an effector of a disposable loading unit inaccordance with at least one alternative embodiment;

FIG. 383 is a top perspective view of the tissue thickness compensatorapplicator of FIG. 382;

FIG. 384 is a bottom perspective view of the tissue thicknesscompensator applicator of FIG. 382;

FIG. 385 is an elevational view of a disposable loading unit including apivotable jaw configured to support a staple cartridge;

FIG. 386 is a cross-sectional view of a staple cartridge comprising atissue thickness compensator attached to a support portion of the staplecartridge in accordance with at least one embodiment;

FIG. 387 is a cross-sectional view of a staple cartridge comprising atissue thickness compensator attached to a support portion of the staplecartridge in accordance with at least one embodiment;

FIG. 388 is a cross-sectional view of a staple cartridge comprising atissue thickness compensator attached to a support portion of the staplecartridge in accordance with at least one embodiment;

FIG. 389 is a perspective view of the tissue thickness compensator ofFIG. 387;

FIG. 390 is a cross-sectional schematic of tissue and a tissue thicknesscompensator pierced by an unformed staple illustrating low frictionconditions between the staple and the tissue thickness compensator;

FIG. 391 is a cross-sectional schematic of tissue and a tissue thicknesscompensator captured with the staple entrapment area of a formed stapleillustrating low friction conditions between the staple and the tissuethickness compensator;

FIG. 392 is a plan view of a tissue thickness compensator for use with astaple cartridge assembly illustrating clearance apertures defined inthe tissue thickness compensator according to various embodiments of thepresent disclosure;

FIG. 393 is an exploded perspective view of a tissue thicknesscompensator and a staple cartridge assembly according to variousembodiments of the present disclosure;

FIG. 394 is a partial cross-sectional view of the staple cartridgeassembly of FIG. 393, illustrating unfired staples positioned in staplecavities of a staple cartridge body and partially embedded in a tissuethickness compensator;

FIG. 395 is a partial cross-sectional view of the staple cartridgeassembly of FIG. 393, illustrating fired staples ejected from the staplecavities of the staple cartridge body and formed against an anvil, andfurther illustrating the tissue thickness compensator and tissuecaptured within the staple entrapment area of the formed staples;

FIG. 396 is a cross-sectional perspective view of a staple positioned ina staple cavity of a staple cartridge body according to variousembodiments of the present disclosure;

FIG. 397 is a partial cross-sectional elevation view of the staplecartridge of FIG. 396, illustrating staples in unfired configurationspositioned in staple cavities and partially embedded in a tissuethickness compensator according to various embodiments of the presentdisclosure;

FIG. 398 is a partial cross-sectional elevation view of the staplecartridge of FIG. 396, illustrating a staple in a partially firedconfiguration;

FIG. 399 is a partial cross-sectional elevation view of the staplecartridge of FIG. 396, illustrating staples in fired configurations, andfurther illustrating tissue and the tissue thickness compensatorcaptured within the staple entrapment area of the formed staples;

FIG. 400 is a partial cross-sectional elevation view of a staplecartridge, illustrating staples in unfired configurations positioned instaple cavities and partially embedded in a tissue thickness compensatoraccording to various embodiments of the present disclosure;

FIG. 401 is a partial cross-sectional elevation view of the staplecartridge of FIG. 400, illustrating a staple in a partially firedconfiguration;

FIG. 402 is a partial cross-sectional elevation view of the staplecartridge of FIG. 400, illustrating staples in fired configurations, andfurther illustrating tissue and the tissue thickness compensatorcaptured within the staple entrapment area of the formed staples;

FIG. 403 is a partial cross-sectional elevation view of a staplecartridge, illustrating the staples in unfired configurations positionedin staple cavities and partially embedded in a tissue thicknesscompensator according to various embodiments of the present disclosure;

FIG. 404 is a partial cross-sectional elevation view of the staplecartridge of FIG. 403, illustrating a staple in a partially firedconfiguration;

FIG. 405 is a partial cross-sectional elevation view of the staplecartridge of FIG. 403, illustrating staples in fired configurations, andfurther illustrating tissue and the tissue thickness compensatorcaptured within the staple entrapment area of the formed staples;

FIG. 406 is a partial perspective view of an end effector of a surgicalfastening instrument in accordance with at least one embodimentillustrated with some portions removed and other portions illustrated incross-section; moreover, a cutting member of the end effector isillustrated in a partially advanced position;

FIG. 407 is a partial cross-sectional end view of the end effector ofFIG. 406 illustrated with patient tissue captured between an anvil and atissue thickness compensator of the end effector; moreover, staplesremovably stored within a cartridge body of the end effector areillustrated in an unfired position and the cutting member of the endeffector is illustrated in an unadvanced position which is proximal tothe tissue thickness compensator;

FIG. 408 is a partial cross-sectional end view of the end effector ofFIG. 406 illustrated with the staples in a fired position and thecutting member in a partially advanced position in which the patienttissue has been at least partially transected;

FIG. 409 is a partial cross-sectional end view of the end effector ofFIG. 406 illustrated with the staples in a fired position and thecutting member in an advanced position in which at least a portion ofthe tissue thickness compensator has been transected by the cuttingmember;

FIG. 410 is a partial cross-sectional elevational view of an endeffector of a surgical fastening instrument in accordance with at leastone embodiment illustrated with an anvil of the end effector in an openposition and patient tissue positioned intermediate the anvil and atissue thickness compensator of the end effector; moreover, staplesremovably positioned within a cartridge body of the end effector areillustrated in an unfired position;

FIG. 411 is a partial cross-sectional elevational view of the endeffector of FIG. 410 illustrated with the anvil in a closed position, afiring member in a partially advanced position, and the staples invarious states of deployment including a fully fired position, partiallyfired positions, and an unfired position; moreover, the end effectorincludes a gap setting element configured to limit the travel of theanvil;

FIG. 412 is a perspective view of the end effector of FIG. 410illustrated with the anvil in an open position and a cutting member ofthe end effector in an unadvanced position;

FIG. 413 is a cross-sectional elevational view of the end effector ofFIG. 410 illustrated with the anvil in a closed position, the cuttingmember in a partially advanced position, and the staples illustrated invarious states of deployment including a fully fired position, partiallyfired positions, and an unfired position; moreover, the cutting membercomprises a first cam member engaged with the anvil and a second cammember engaged with the cartridge body to control the gap between theanvil and the tissue thickness compensator of the end effector;

FIG. 414 is a chart plotting the force experienced by a cutting memberto incise a tissue thickness compensator of a fastener cartridgeassembly, such as the fastener cartridge assembly of FIG. 406, forexample, against the stroke length of the cutting member; moreover, theforce required to incise the tissue thickness compensator may alternatebetween pulses of a first resistance and pulses of a second, or lower,resistance;

FIG. 415 is a detail view of a first resistance pulse depicted in FIG.414;

FIG. 416 is a chart plotting the force experienced by the cutting memberdiscussed in connection with FIG. 414 to incise tissue against thestroke length of the cutting member;

FIG. 417 is a chart plotting the drag force experienced by the cuttingmember discussed in connection with FIG. 414 as the cutting memberpasses through the tissue thickness compensator against the strokelength of the cutting member;

FIG. 418 is a chart plotting the drag force experienced by the cuttingmember discussed in connection with FIG. 414 as the cutting memberpasses through the tissue discussed in connection with FIG. 416 againstthe stroke length of the cutting member;

FIG. 419 is a plan view of a tissue thickness compensator in accordancewith at least one embodiment;

FIG. 420 is a perspective view of a fastener cartridge including atissue thickness compensator in accordance with at least one embodiment;and

FIG. 421 is a cross-sectional view of the tissue thickness compensatorof FIG. 420 illustrating a cutting member positioned relative to aproximal end of the tissue thickness compensator.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate certain embodiments of the invention, in one form, and suchexemplifications are not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

The Applicant of the present application also owns the U.S. patentapplications identified below which are each herein incorporated byreference in their respective entirety:

U.S. patent application Ser. No. 12/894,311, entitled SURGICALINSTRUMENTS WITH RECONFIGURABLE SHAFT SEGMENTS, now U.S. PatentPublication No. 2012/0080496;

U.S. patent application Ser. No. 12/894,340, entitled SURGICAL STAPLECARTRIDGES SUPPORTING NON-LINEARLY ARRANGED STAPLES AND SURGICALSTAPLING INSTRUMENTS WITH COMMON STAPLE-FORMING POCKETS, now U.S. PatentPublication No. 2012/0080482;

U.S. patent application Ser. No. 12/894,327, entitled JAW CLOSUREARRANGEMENTS FOR SURGICAL INSTRUMENTS, now U.S. Patent Publication No.2012/0080499;

U.S. patent application Ser. No. 12/894,351, entitled SURGICAL CUTTINGAND FASTENING INSTRUMENTS WITH SEPARATE AND DISTINCT FASTENER DEPLOYMENTAND TISSUE CUTTING SYSTEMS, now U.S. Patent Publication No.2012/0080502;

U.S. patent application Ser. No. 12/894,338, entitled IMPLANTABLEFASTENER CARTRIDGE HAVING A NON-UNIFORM ARRANGEMENT, now U.S. PatentPublication No. 2012/0080481;

U.S. patent application Ser. No. 12/894,369, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING A SUPPORT RETAINER, now U.S. PatentPublication No. 2012/0080344;

U.S. patent application Ser. No. 12/894,312, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING MULTIPLE LAYERS, now U.S. PatentPublication No. 2012/0080479;

U.S. patent application Ser. No. 12/894,377, entitled SELECTIVELYORIENTABLE IMPLANTABLE FASTENER CARTRIDGE, now U.S. Patent PublicationNo. 2012/0080334;

U.S. patent application Ser. No. 12/894,339, entitled SURGICAL STAPLINGINSTRUMENT WITH COMPACT ARTICULATION CONTROL ARRANGEMENT, now U.S.Patent Publication No. 2012/0080500;

U.S. patent application Ser. No. 12/894,360, entitled SURGICAL STAPLINGINSTRUMENT WITH A VARIABLE STAPLE FORMING SYSTEM, now U.S. PatentPublication No. 2012/0080484;

U.S. patent application Ser. No. 12/894,322, entitled SURGICAL STAPLINGINSTRUMENT WITH INTERCHANGEABLE STAPLE CARTRIDGE ARRANGEMENTS, now U.S.Patent Publication No. 2012/0080501;

U.S. patent application Ser. No. 12/894,350, entitled SURGICAL STAPLECARTRIDGES WITH DETACHABLE SUPPORT STRUCTURES AND SURGICAL STAPLINGINSTRUMENTS WITH SYSTEMS FOR PREVENTING ACTUATION MOTIONS WHEN ACARTRIDGE IS NOT PRESENT, now U.S. Patent Publication No. 2012/0080478;

U.S. patent application Ser. No. 12/894,383, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING BIOABSORBABLE LAYERS, now U.S. PatentPublication No. 2012/0080345;

U.S. patent application Ser. No. 12/894,389, entitled COMPRESSIBLEFASTENER CARTRIDGE, now U.S. Patent Publication No. 2012/0080335;

U.S. patent application Ser. No. 12/894,345, entitled FASTENERSSUPPORTED BY A FASTENER CARTRIDGE SUPPORT, now U.S. Patent PublicationNo. 2012/0080483;

U.S. patent application Ser. No. 12/894,306, entitled COLLAPSIBLEFASTENER CARTRIDGE, now U.S. Patent Publication No. 2012/0080332;

U.S. patent application Ser. No. 12/894,318, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF CONNECTED RETENTION MATRIX ELEMENTS, now U.S.Patent Publication No. 2012/0080480;

U.S. patent application Ser. No. 12/894,330, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND AN ALIGNMENT MATRIX, now U.S. PatentPublication No. 2012/0080503;

U.S. patent application Ser. No. 12/894,361, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX, now U.S. Patent Publication No.2012/0080333;

U.S. patent application Ser. No. 12/894,367, entitled FASTENINGINSTRUMENT FOR DEPLOYING A FASTENER SYSTEM COMPRISING A RETENTIONMATRIX, now U.S. Patent Publication No. 2012/0080485;

U.S. patent application Ser. No. 12/894,388, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND A COVER, now U.S. Patent PublicationNo. 2012/0080487;

U.S. patent application Ser. No. 12/894,376, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF FASTENER CARTRIDGES, now U.S. PatentPublication No. 2012/0080486;

U.S. patent application Ser. No. 13/097,865, entitled SURGICAL STAPLERANVIL COMPRISING A PLURALITY OF FORMING POCKETS, now U.S. PatentPublication No. 2012/0080488;

U.S. patent application Ser. No. 13/097,936, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER, now U.S. Patent Publication No.2012/0080339;

U.S. patent application Ser. No. 13/097,954, entitled STAPLE CARTRIDGECOMPRISING A VARIABLE THICKNESS COMPRESSIBLE PORTION, now U.S. PatentPublication No. 2012/0080340;

U.S. patent application Ser. No. 13/097,856, entitled STAPLE CARTRIDGECOMPRISING STAPLES POSITIONED WITHIN A COMPRESSIBLE PORTION THEREOF, nowU.S. Patent Publication No. 2012/0080336;

U.S. patent application Ser. No. 13/097,928, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING DETACHABLE PORTIONS, now U.S. Patent PublicationNo. 2012/0080490;

U.S. patent application Ser. No. 13/097,891, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER COMPRISING AN ADJUSTABLE ANVIL, nowU.S. Patent Publication No. 2012/0080489;

U.S. patent application Ser. No. 13/097,948, entitled STAPLE CARTRIDGECOMPRISING AN ADJUSTABLE DISTAL PORTION, now U.S. Patent Publication No.2012/0083836;

U.S. patent application Ser. No. 13/097,907, entitled COMPRESSIBLESTAPLE CARTRIDGE ASSEMBLY, now U.S. Patent Publication No. 2012/0080338;

U.S. patent application Ser. No. 13/097,861, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING PORTIONS HAVING DIFFERENT PROPERTIES, now U.S.Patent Publication No. 2012/0080337;

U.S. patent application Ser. No. 13/097,869, entitled STAPLE CARTRIDGELOADING ASSEMBLY, now U.S. Patent Publication No. 2012/0160721;

U.S. patent application Ser. No. 13/097,917, entitled COMPRESSIBLESTAPLE CARTRIDGE COMPRISING ALIGNMENT MEMBERS, now U.S. PatentPublication No. 2012/0083834;

U.S. patent application Ser. No. 13/097,873, entitled STAPLE CARTRIDGECOMPRISING A RELEASABLE PORTION, now U.S. Patent Publication No.2012/0083833;

U.S. patent application Ser. No. 13/097,938, entitled STAPLE CARTRIDGECOMPRISING COMPRESSIBLE DISTORTION RESISTANT COMPONENTS, now U.S. PatentPublication No. 2012/0080491;

U.S. patent application Ser. No. 13/097,924, entitled STAPLE CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR, now U.S. Patent PublicationNo. 2012/0083835;

U.S. patent application Ser. No. 13/242,029, entitled SURGICAL STAPLERWITH FLOATING ANVIL, now U.S. Patent Publication No. 2012/0080493;

U.S. patent application Ser. No. 13/242,066, entitled CURVED ENDEFFECTOR FOR A STAPLING INSTRUMENT, now U.S. Patent Publication No.2012/0080498;

U.S. patent application Ser. No. 13/242,086, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK;

U.S. patent application Ser. No. 13/241,912, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK ARRANGEMENT;

U.S. patent application Ser. No. 13/241,922, entitled SURGICAL STAPLERWITH STATIONARY STAPLE DRIVERS;

U.S. patent application Ser. No. 13/241,637, entitled SURGICALINSTRUMENT WITH TRIGGER ASSEMBLY FOR GENERATING MULTIPLE ACTUATIONMOTIONS, now U.S. Patent Publication No. 2012/0074201;

U.S. patent application Ser. No. 13/241,629, entitled SURGICALINSTRUMENT WITH SELECTIVELY ARTICULATABLE END EFFECTOR, now U.S. PatentPublication No. 2012/0074200;

U.S. application Ser. No. 13/433,096, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF CAPSULES, now U.S. PatentPublication No. 2012/0241496;

U.S. application Ser. No. 13/433,103, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF LAYERS, now U.S. PatentPublication No. 2012/0241498;

U.S. application Ser. No. 13/433,098, entitled EXPANDABLE TISSUETHICKNESS COMPENSATOR, now U.S. Patent Publication No. 2012/0241491;

U.S. application Ser. No. 13/433,102, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A RESERVOIR, now U.S. Patent Publication No.2012/0241497;

U.S. application Ser. No. 13/433,114, entitled RETAINER ASSEMBLYINCLUDING A TISSUE THICKNESS COMPENSATOR, now U.S. Patent PublicationNo. 2012/0241499;

U.S. application Ser. No. 12/433,136, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING AT LEAST ONE MEDICAMENT, now U.S. PatentPublication No. 2012/0241492;

U.S. application Ser. No. 13/433,141, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CONTROLLED RELEASE AND EXPANSION, now U.S. PatentPublication No. 2012/0241493;

U.S. application Ser. No. 13/433,144, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING FIBERS TO PRODUCE A RESILIENT LOAD, now U.S.Patent Publication No. 2012/0241500;

U.S. application Ser. No. 13/433,148, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING STRUCTURE TO PRODUCE A RESILIENT LOAD, now U.S.Patent Publication No. 2012/0241501;

U.S. application Ser. No. 13/433,155, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING RESILIENT MEMBERS, now U.S. Patent PublicationNo. 2012/0241502;

U.S. application Ser. No. 13/433,163, entitled METHODS FOR FORMINGTISSUE THICKNESS COMPENSATOR ARRANGEMENTS FOR SURGICAL STAPLERS, nowU.S. Patent Publication No. 2012/0248169;

U.S. application Ser. No. 13/433,167, entitled TISSUE THICKNESSCOMPENSATORS, now U.S. Patent Publication No. 2012/0241503;

U.S. application Ser. No. 13/433,175, entitled LAYERED TISSUE THICKNESSCOMPENSATOR, now U.S. Patent Publication No. 2012/0253298;

U.S. application Ser. No. 13/433,179, entitled TISSUE THICKNESSCOMPENSATORS FOR CIRCULAR SURGICAL STAPLERS, now U.S. Patent PublicationNo. 2012/0241505;

U.S. application Ser. No. 13/433,115, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CAPSULES DEFINING A LOW PRESSURE ENVIRONMENT;

U.S. application Ser. No. 13/433,118, entitled TISSUE THICKNESSCOMPENSATOR COMPRISED OF A PLURALITY OF MATERIALS;

U.S. application Ser. No. 13/433,135, entitled MOVABLE MEMBER FOR USEWITH A TISSUE THICKNESS COMPENSATOR;

U.S. application Ser. No. 13/433,140, entitled TISSUE THICKNESSCOMPENSATOR AND METHOD FOR MAKING THE SAME;

U.S. application Ser. No. 13/433,147, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CHANNELS;

U.S. application Ser. No. 13/433,126, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING TISSUE INGROWTH FEATURES;

U.S. application Ser. No. 13/433,132, entitled DEVICES AND METHODS FORATTACHING TISSUE THICKNESS COMPENSATING MATERIALS TO SURGICAL STAPLINGINSTRUMENTS;

U.S. application Ser. No. 13/433,129, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF MEDICAMENTS.

U.S. application Ser. No. 11/216,562, entitled STAPLE CARTRIDGES FORFORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. Pat.No. 7,669,746;

U.S. application Ser. No. 11/714,049, entitled SURGICAL STAPLING DEVICEWITH ANVIL HAVING STAPLE FORMING POCKETS OF VARYING DEPTHS, now U.S.Patent Publication No. 2007/0194082;

U.S. application Ser. No. 11/711,979, entitled SURGICAL STAPLING DEVICESTHAT PRODUCE FORMED STAPLES HAVING DIFFERENT LENGTHS, now U.S. Pat. No.8,317,070;

U.S. application Ser. No. 11/711,975, entitled SURGICAL STAPLING DEVICEWITH STAPLE DRIVERS OF DIFFERENT HEIGHT, now U.S. Patent Publication No.2007/0194079;

U.S. application Ser. No. 11/711,977, entitled SURGICAL STAPLING DEVICEWITH STAPLE DRIVER THAT SUPPORTS MULTIPLE WIRE DIAMETER STAPLES, nowU.S. Pat. No. 7,673,781;

U.S. application Ser. No. 11/712,315, entitled SURGICAL STAPLING DEVICEWITH MULTIPLE STACKED ACTUATOR WEDGE CAMS FOR DRIVING STAPLE DRIVERS,now U.S. Pat. No. 7,500,979;

U.S. application Ser. No. 12/038,939, entitled STAPLE CARTRIDGES FORFORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. Pat.No. 7,934,630;

U.S. application Ser. No. 13/020,263, entitled SURGICAL STAPLING SYSTEMSTHAT PRODUCE FORMED STAPLES HAVING DIFFERENT LENGTHS, now U.S. PatentPublication No. 2011/0147434;

U.S. application Ser. No. 13/118,278, entitled ROBOTICALLY-CONTROLLEDSURGICAL STAPLING DEVICES THAT PRODUCE FORMED STAPLES HAVING DIFFERENTLENGTHS, now U.S. Patent Publication No. 2011/0290851;

U.S. application Ser. No. 13/369,629, entitled ROBOTICALLY-CONTROLLEDCABLE-BASED SURGICAL END EFFECTORS, now U.S. Patent Publication No.2012/0138660;

U.S. application Ser. No. 12/695,359, entitled SURGICAL STAPLING DEVICESFOR FORMING STAPLES WITH DIFFERENT FORMED HEIGHTS, now U.S. PatentPublication No. 2010/0127042;

U.S. application Ser. No. 13/072,923, entitled STAPLE CARTRIDGES FORFORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. PatentPublication No. 2011/0174863;

U.S. application Ser. No. 13/763,112, entitled SURGICAL STAPLINGCARTRIDGE WITH LAYER RETENTION FEATURES;

U.S. application Ser. No. 13/763,035, entitled ACTUATOR FOR RELEASING ATISSUE THICKNESS COMPENSATOR FROM A FASTENER CARTRIDGE;

U.S. application Ser. No. 13/763,042, entitled RELEASABLE TISSUETHICKNESS COMPENSATOR AND FASTENER CARTRIDGE HAVING THE SAME;

U.S. application Ser. No. 13/763,048, entitled FASTENER CARTRIDGECOMPRISING A RELEASABLE TISSUE THICKNESS COMPENSATOR;

U.S. application Ser. No. 13/763,054, entitled FASTENER CARTRIDGECOMPRISING A CUTTING MEMBER FOR RELEASING A TISSUE THICKNESSCOMPENSATOR;

U.S. application Ser. No. 13/763,065, entitled FASTENER CARTRIDGECOMPRISING A RELEASABLY ATTACHED TISSUE THICKNESS COMPENSATOR;

U.S. application Ser. No. 13/763,021, entitled STAPLE CARTRIDGECOMPRISING A RELEASABLE COVER;

U.S. application Ser. No. 13/763,078, entitled ANVIL LAYER ATTACHED TO APROXIMAL END OF AN END EFFECTOR;

U.S. application Ser. No. 13/763,094, entitled LAYER COMPRISINGDEPLOYABLE ATTACHMENT MEMBERS;

U.S. application Ser. No. 13/763,106, entitled END EFFECTOR COMPRISING ADISTAL TISSUE ABUTMENT MEMBER;

U.S. application Ser. No. 13/763,095, entitled LAYER ARRANGEMENTS FORSURGICAL STAPLE CARTRIDGES;

U.S. application Ser. No. 13/463,147, entitled IMPLANTABLE ARRANGEMENTSFOR SURGICAL STAPLE CARTRIDGES;

U.S. application Ser. No. 13/763,192, entitled MULTIPLE THICKNESSIMPLANTABLE LAYERS FOR SURGICAL STAPLING DEVICES;

U.S. application Ser. No. 13/763,161, entitled RELEASABLE LAYER OFMATERIAL AND SURGICAL END EFFECTOR HAVING THE SAME;

U.S. application Ser. No. 13/763,177, entitled ACTUATOR FOR RELEASING ALAYER OF MATERIAL FROM A SURGICAL END EFFECTOR;

U.S. application Ser. No. 13/763,037, entitled STAPLE CARTRIDGECOMPRISING A COMPRESSIBLE PORTION; and

U.S. application Ser. No. 13/763,028, entitled STAPLE CARTRIDGECOMPRISING A COMPRESSIBLE PORTION.

The Applicant of the present application also owns the U.S. patentapplications identified below which were filed on even date herewith andwhich are each herein incorporated by reference in their respectiveentirety:

U.S. application Ser. No. ______, entitled TISSUE THICKNESS COMPENSATORCOMPRISING A CUTTING MEMBER PATH, (Attorney Docket No.END7270USNP/130101);

U.S. application Ser. No. ______, entitled FASTENER CARTRIDGEASSEMBLIES, (Attorney Docket No. END7271USNP/130102); and

U.S. application Ser. No. ______, entitled FASTENER CARTRIDGE COMPRISINGA TISSUE THICKNESS COMPENSATOR AND A GAP SETTING ELEMENT, (AttorneyDocket No. END7272USNP/130103).

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those of ordinary skill in the art will understand that thedevices and methods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the various embodiments of the present invention is definedsolely by the claims. The features illustrated or described inconnection with one exemplary embodiment may be combined with thefeatures of other embodiments. Such modifications and variations areintended to be included within the scope of the present invention.

Reference throughout the specification to “various embodiments,” “someembodiments,” “one embodiment,” or “an embodiment”, or the like, meansthat a particular feature, structure, or characteristic described inconnection with the embodiment is included in at least one embodiment.Thus, appearances of the phrases “in various embodiments,” “in someembodiments,” “in one embodiment”, or “in an embodiment”, or the like,in places throughout the specification are not necessarily all referringto the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments. Thus, the particular features, structures, orcharacteristics illustrated or described in connection with oneembodiment may be combined, in whole or in part, with the featuresstructures, or characteristics of one or more other embodiments withoutlimitation. Such modifications and variations are intended to beincluded within the scope of the present invention.

The terms “proximal” and “distal” are used herein with reference to aclinician manipulating the handle portion of the surgical instrument.The term “proximal” referring to the portion closest to the clinicianand the term “distal” referring to the portion located away from theclinician. It will be further appreciated that, for convenience andclarity, spatial terms such as “vertical”, “horizontal”, “up”, and“down” may be used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and/or absolute.

Various exemplary devices and methods are provided for performinglaparoscopic and minimally invasive surgical procedures. However, theperson of ordinary skill in the art will readily appreciate that thevarious methods and devices disclosed herein can be used in numeroussurgical procedures and applications including, for example, inconnection with open surgical procedures. As the present DetailedDescription proceeds, those of ordinary skill in the art will furtherappreciate that the various instruments disclosed herein can be insertedinto a body in any way, such as through a natural orifice, through anincision or puncture hole formed in tissue, etc. The working portions orend effector portions of the instruments can be inserted directly into apatient's body or can be inserted through an access device that has aworking channel through which the end effector and elongated shaft of asurgical instrument can be advanced.

Turning to the Drawings wherein like numerals denote like componentsthroughout the several views, FIG. 1 depicts a surgical instrument 10that is capable of practicing several unique benefits. The surgicalstapling instrument 10 is designed to manipulate and/or actuate variousforms and sizes of end effectors 12 that are operably attached thereto.In the embodiment depicted in FIGS. 1-1E, for example, the end effector12 includes an elongated channel 14 that forms a lower jaw 13 of the endeffector 12. The elongated channel 14 is configured to support an“implantable” staple cartridge 30 and also movably support an anvil 20that functions as an upper jaw 15 of the end effector 12.

In various embodiments, the elongated channel 14 may be fabricated from,for example, 300 & 400 Series, 17-4 & 17-7 stainless steel, titanium,etc. and be formed with spaced side walls 16. The anvil 20 may befabricated from, for example, 300 & 400 Series, 17-4 & 17-7 stainlesssteel, titanium, etc. and have a staple forming undersurface, generallylabeled as 22 that has a plurality of staple forming pockets 23 formedtherein. See FIGS. 1B-1E. In addition, the anvil 20 has a bifurcatedramp assembly 24 that protrudes proximally therefrom. An anvil pin 26protrudes from each lateral side of the ramp assembly 24 to be receivedwithin a corresponding slot or opening 18 in the side walls 16 of theelongated channel 14 to facilitate its movable or pivotable attachmentthereto.

Various forms of implantable staple cartridges may be employed with thevarious embodiments of the surgical instruments disclosed herein.Specific staple cartridge configurations and constructions will bediscussed in further detail below. However, in the embodiment depictedin FIG. 1A, an implantable staple cartridge 30 is shown. In at least oneembodiment, the staple cartridge 30 has a body portion 31 that consistsof a compressible hemostat material such as, for example, oxidizedregenerated cellulose (“ORC”) or a bio-absorbable foam in which lines ofunformed metal staples 32 are supported. In at least some embodiments,in order to prevent the staple from being affected and the hemostatmaterial from being activated during the introduction and positioningprocess, the entire cartridge may be coated or wrapped in abiodegradable film 38 such as a polydioxanon film sold under thetrademark PDS® or with a Polyglycerol sebacate (PGS) film or otherbiodegradable films formed from PGA (Polyglycolic acid, marketed underthe trade mark Vicryl), PCL (Polycaprolactone), PLA or PLLA (Polylacticacid), PHA (polyhydroxyalkanoate), PGCL (poliglecaprone 25, sold underthe trademark Monocryl) or a composite of PGA, PCL, PLA, PDS that wouldbe impermeable until ruptured. The body 31 of staple cartridge 30 issized to be removably supported within the elongated channel 14 as shownsuch that each staple 32 therein is aligned with corresponding stapleforming pockets 23 in the anvil when the anvil 20 is driven into formingcontact with the staple cartridge 30.

In use, once the end effector 12 has been positioned adjacent the targettissue, the end effector 12 is manipulated to capture or clamp thetarget tissue between an upper face 36 of the staple cartridge 30 andthe staple forming surface 22 of the anvil 20. The staples 32 are formedby moving the anvil 20 in a path that is substantially parallel to theelongated channel 14 to bring the staple forming surface 22 and, moreparticularly, the staple forming pockets 23 therein into substantiallysimultaneous contact with the upper face 36 of the staple cartridge 30.As the anvil 20 continues to move into the staple cartridge 30, the legs34 of the staples 32 contact a corresponding staple forming pocket 23 inanvil 20 which serves to bend the staple legs 34 over to form thestaples 32 into a “B shape”. Further movement of the anvil 20 toward theelongated channel 14 will further compress and form the staples 32 to adesired final formed height “FF”.

The above-described staple forming process is generally depicted inFIGS. 1B-1E. For example, FIG. 1B illustrates the end effector 12 withtarget tissue “T” between the anvil 20 and the upper face 36 of theimplantable staple cartridge 30. FIG. 1C illustrates the initialclamping position of the anvil 20 wherein the anvil has 20 been closedonto the target tissue “T” to clamp the target tissue “T” between theanvil 20 and the upper face 36 of the staple cartridge 30. FIG. 1Dillustrates the initial staple formation wherein the anvil 20 hasstarted to compress the staple cartridge 30 such that the legs 34 of thestaples 32 are starting to be formed by the staple forming pockets 23 inthe anvil 20. FIG. 1E illustrates the staple 32 in its final formedcondition through the target tissue “T” with the anvil 20 removed forclarity purposes. Once the staples 32 have been formed and fastened tothe target tissue “T”, the surgeon will move the anvil 20 to the openposition to enable the cartridge body 31 and the staples 32 to remainaffixed to the target tissue while the end effector 12 is beingwithdrawn from the patient. The end effector 12 forms all of the staplessimultaneously as the two jaws 13, 15 are clamped together. Theremaining “crushed” body materials 31 act as both a hemostat (the ORC)and a staple line reinforcement (PGA, PDS or any of the other filmcompositions mentioned above 38). Also, since the staples 32 never haveto leave the cartridge body 31 during forming, the likelihood of thestaples 32 being malformed during forming is minimized. As used hereinthe term “implantable” means that, in addition to the staples, thecartridge body materials that support the staples will also remain inthe patient and may eventually be absorbed by the patient's body. Suchimplantable staple cartridges are distinguishable from prior cartridgearrangements that remain positioned within the end effector in theirentirety after they have been fired.

In various implementations, the end effector 12 is configured to becoupled to an elongated shaft assembly 40 that protrudes from a handleassembly 100. The end effector 12 (when closed) and the elongated shaftassembly 40 may have similar cross-sectional shapes and be sized tooperably pass through a trocar tube or working channel in another formof access instrument. As used herein, the term “operably pass” meansthat the end effector and at least a portion of the elongated shaftassembly may be inserted through or passed through the channel or tubeopening and can be manipulated therein as needed to complete thesurgical stapling procedure. In some embodiments, when in a closedposition, the jaws 13 and 15 of the end effector 12 may provide the endeffector with a roughly circular cross-sectional shape that facilitatesits passage through a circular passage/opening. However, the endeffectors of various embodiments of the present invention, as well asthe elongated shaft assembly embodiments, could conceivably be providedwith other cross-sectional shapes that could otherwise pass throughaccess passages and openings that have non-circular cross-sectionalshapes. Thus, an overall size of a cross-section of a closed endeffector will be related to the size of the passage or opening throughwhich it is intended to pass. Thus, one end effector for example, may bereferred to as a “5 mm” end effector which means it can operably passthrough an opening that is at least approximately 5 mm in diameter.

In various embodiments, the elongated shaft assembly 40 may have anouter diameter that is substantially the same as the outer diameter ofthe end effector 12 when in a closed position. For example, a 5 mm endeffector may be coupled to an elongated shaft assembly 40 that has 5 mmcross-sectional diameter. However, as the present Detailed Descriptionproceeds, it will become apparent that various embodiments of thepresent may be effectively used in connection with different sizes ofend effectors. For example, a 10 mm end effector may be attached to anelongated shaft that has a 5 mm cross-sectional diameter. Conversely,for those applications wherein a 10 mm or larger access opening orpassage is provided, the elongated shaft assembly 40 may have a 10 mm(or larger) cross-sectional diameter, but may also be able to actuate a5 mm or 10 mm end effector. Accordingly, the outer shaft 40 may have anouter diameter that is the same as or is different from the outerdiameter of a closed end effector 12 attached thereto.

As depicted, the elongated shaft assembly 40 extends distally from thehandle assembly 100 in a generally straight line to define alongitudinal axis A-A. In various embodiments, for example, theelongated shaft assembly 40 may be approximately 9-16 inches (229-406mm) long. However, the elongated shaft assembly 40 may be provided inother lengths and, in other embodiments, may have joints therein or beotherwise configured to facilitate articulation of the end effector 12relative to other portions of the shaft or handle assembly as will bediscussed in further detail below. In various embodiments, the elongatedshaft assembly 40 includes a spine member 50 that extends from thehandle assembly 100 to the end effector 12. The proximal end of theelongated channel 14 of the end effector 12 has a pair of retentiontrunnions 17 protruding therefrom that are sized to be received withincorresponding trunnion openings or cradles 52 that are provided in adistal end of the spine member 50 to enable the end effector 12 to beremovably coupled the elongated shaft assembly 40. The spine member 50may be fabricated from, for example, 6061 or 7075 aluminum, stainlesssteel, titanium, etc.

In various embodiments, the handle assembly 100 comprises a pistolgrip-type housing that may be fabricated in two or more pieces forassembly purposes. For example, the handle assembly 100 as showncomprises a right hand case member 102 and a left hand case member (notillustrated) that are molded or otherwise fabricated from a polymer orplastic material and are designed to mate together. Such case membersmay be attached together by snap features, pegs and sockets molded orotherwise formed therein and/or by adhesive, screws, etc. The spinemember 50 has a proximal end 54 that has a flange 56 formed thereon. Theflange 56 is configured to be rotatably supported within a groove 106formed by mating ribs 108 that protrude inwardly from each of the casemembers 102, 104. Such arrangement facilitates the attachment of thespine member 50 to the handle assembly 100 while enabling the spinemember 50 to be rotated relative to the handle assembly 100 about thelongitudinal axis A-A in a 360° path.

As can be further seen in FIG. 1, the spine member 50 passes through andis supported by a mounting bushing 60 that is rotatably affixed to thehandle assembly 100. The mounting bushing 60 has a proximal flange 62and a distal flange 64 that define a rotational groove 65 that isconfigured to rotatably receive a nose portion 101 of the handleassembly 100 therebetween. Such arrangement enables the mounting bushing60 to rotate about longitudinal axis A-A relative to the handle assembly100. The spine member 50 is non-rotatably pinned to the mounting bushing60 by a spine pin 66. In addition, a rotation knob 70 is attached to themounting bushing 60. In one embodiment, for example, the rotation knob70 has a hollow mounting flange portion 72 that is sized to receive aportion of the mounting bushing 60 therein. In various embodiments, therotation knob 70 may be fabricated from, for example, glass or carbonfilled Nylon, polycarbonate, Ultem®, etc. and is affixed to the mountingbushing 60 by the spine pin 66 as well. In addition, an inwardlyprotruding retention flange 74 is formed on the mounting flange portion72 and is configured to extend into a radial groove 68 formed in themounting bushing 60. Thus, the surgeon may rotate the spine member 50(and the end effector 12 attached thereto) about longitudinal axis A-Ain a 360° path by grasping the rotation knob 70 and rotating it relativeto the handle assembly 100.

In various embodiments, the anvil 20 is retained in an open position byan anvil spring 21 and/or another biasing arrangement. The anvil 20 isselectively movable from the open position to various closed or clampingand firing positions by a firing system, generally designated as 109.The firing system 109 includes a “firing member” 110 which, in variousembodiments, comprises a hollow firing tube 110. The hollow firing tube110 is axially movable on the spine member 50 and thus forms the outerportion of the elongated shaft assembly 40. The firing tube 110 may befabricated from a polymer or other suitable material and have a proximalend that is attached to a firing yoke 114 of the firing system 109. Invarious embodiments for example, the firing yoke 114 may be over-moldedto the proximal end of the firing tube 110. However, other fastenerarrangements may be employed.

As can be seen in FIG. 1, the firing yoke 114 may be rotatably supportedwithin a support collar 120 that is configured to move axially withinthe handle assembly 100. In various embodiments, the support collar 120has a pair of laterally extending fins that are sized to be slidablyreceived within fin slots formed in the right and left hand casemembers. Thus, the support collar 120 may slide axially within thehandle housing 100 while enabling the firing yoke 114 and firing tube110 to rotate relative thereto about the longitudinal axis A-A. Invarious embodiments, a longitudinal slot is provided through the firingtube 110 to enable the spine pin 66 to extend therethrough into thespine member 50 while facilitating the axial travel of the firing tube110 on the spine member 50.

The firing system 109 further comprises a firing trigger 130 whichserves to control the axial travel of the firing tube 110 on the spinemember 50. See FIG. 1. Such axial movement in the distal direction ofthe firing tube 110 into firing interaction with the anvil 20 isreferred to herein as “firing motion”. As can be seen in FIG. 1, thefiring trigger 130 is movably or pivotally coupled to the handleassembly 100 by a pivot pin 132. A torsion spring 135 is employed tobias the firing trigger 130 away from the pistol grip portion 107 of thehandle assembly 100 to an un-actuated “open” or starting position. Ascan be seen in FIG. 1, the firing trigger 130 has an upper portion 134that is movably attached to (pinned) firing links 136 that are movablyattached to (pinned) the support collar 120. Thus, movement of thefiring trigger 130 from the starting position (FIG. 1) toward an endingposition adjacent the pistol grip portion 107 of the handle assembly 100will cause the firing yoke 114 and the firing tube 110 to move in thedistal direction “DD”. Movement of the firing trigger 130 away from thepistol grip portion 107 of the handle assembly 100 (under the bias ofthe torsion spring 135) will cause the firing yoke 114 and firing tube110 to move in the proximal direction “PD” on the spine member 50.

Various embodiments of the present invention may be employed withdifferent sizes and configurations of implantable staple cartridges. Forexample, the surgical instrument 10, when used in connection with afirst firing adapter 140, may be used with a 5 mm end effector 12 thatis approximately 20 mm long (or in other lengths) which supports animplantable staple cartridge 30. Such end effector size may beparticularly well-suited, for example, to complete relatively finedissection and vascular transactions. However, as will be discussed infurther detail below, the surgical instrument 10 may also be employed,for example, in connection with other sizes of end effectors and staplecartridges by replacing the first firing adapter 140 with a secondfiring adapter. In still other embodiments, the elongated shaft assembly40 may configured to be attached to only one form or size of endeffector.

One method of removably coupling the end effector 12 to the spine member50 will now be explained. The coupling process is commenced by insertingthe retention trunnions 17 on the elongated channel 14 into the trunnioncradles 52 in the spine member 50. Thereafter, the surgeon advances thefiring trigger 130 toward the pistol grip 107 of the housing assembly100 to distally advance the firing tube 110 and the first firing adapter140 over a proximal end portion 47 of the elongated channel 14 tothereby retain the trunnions 17 in their respective cradles 52. Suchposition of the first firing adapter 140 over the trunnions 17 isreferred to herein as the “coupled position”. Various embodiments of thepresent invention may also have an end effector locking assembly forlocking the firing trigger 130 in position after an end effector 12 hasbeen attached to the spine member 50.

More specifically, one embodiment of the end effector locking assembly160 includes a retention pin 162 that is movably supported in the upperportion 134 of the firing trigger 130. As discussed above, the firingtube 110 must initially be advanced distally to the coupled positionwherein the first firing adapter 140 retains the retention trunnions 17of the end effector 12 in the trunnion cradles 52 in the spine member50. The surgeon advances the firing adapter 140 distally to the coupledposition by pulling the firing trigger 130 from the starting positiontoward the pistol grip 107. As the firing trigger 130 is initiallyactuated, the retention pin 162 is moved distally until the firing tube110 has advanced the first firing adapter 140 to the coupled position atwhich point the retention pin 162 is biased into a locking cavity 164formed in the case member. In various embodiments, when the retentionpin 162 enters into the locking cavity 164, the pin 162 may make anaudible “click” or other sound, as well as provide a tactile indicationto the surgeon that the end effector 12 has been “locked” onto the spinemember 50. In addition, the surgeon cannot inadvertently continue toactuate the firing trigger 130 to start to form staples 32 in the endeffector 12 without intentionally biasing the retention pin 162 out ofthe locking cavity 164. Similarly, if the surgeon releases the firingtrigger 130 when in the coupled position, it is retained in thatposition by the retention pin 162 to prevent the firing trigger 130 fromreturning to the starting position and thereby releasing the endeffector 12 from the spine member 50.

Various embodiments of the present invention may further include afiring system lock button 137 that is pivotally attached to the handleassembly 100. In one form, the firing system lock button 137 has a latch138 formed on a distal end thereof that is oriented to engage the firingyoke 114 when the firing release button is in a first latching position.As can be seen in FIG. 1, a latch spring 139 serves to bias the firingsystem lock button 137 to the first latching position. In variouscircumstances, the latch 138 serves to engage the firing yoke 114 at apoint where the position of the firing yoke 114 on the spine member 50corresponds to a point wherein the first firing adapter 140 is about todistally advance up the clamping ramp 28 on the anvil 20. It will beunderstood that, as the first firing adapter 140 advances axially up theclamping ramp 28, the anvil 20 will move in a path such that its stapleforming surface portion 22 is substantially parallel to the upper face36 of the staple cartridge 30.

After the end effector 12 has been coupled to the spine member 50, thestaple forming process is commenced by first depressing the firingsystem lock button 137 to enable the firing yoke 114 to be further moveddistally on the spine member 50 and ultimately compress the anvil 20into the staple cartridge 30. After depressing the firing system lockbutton 137, the surgeon continues to actuate the firing trigger 130towards the pistol grip 107 thereby driving the first staple collar 140up the corresponding staple forming ramp 29 to force the anvil 20 intoforming contact with the staples 32 in the staple cartridge 30. Thefiring system lock button 137 prevents the inadvertent forming of thestaples 32 until the surgeon is ready to start that process. In thisembodiment, the surgeon must depress the firing system lock button 137before the firing trigger 130 may be further actuated to begin thestaple forming process.

The surgical instrument 10 may be solely used as a tissue staplingdevice if so desired. However, various embodiments of the presentinvention may also include a tissue cutting system, generally designatedas 170. In at least one form, the tissue cutting system 170 comprises aknife member 172 that may be selectively advanced from an un-actuatedposition adjacent the proximal end of the end effector 12 to an actuatedposition by actuating a knife advancement trigger 200. The knife member172 is movably supported within the spine member 50 and is attached orotherwise protrudes from a knife rod 180. The knife member 172 may befabricated from, for example, 420 or 440 stainless steel with a hardnessof greater than 38HRC (Rockwell Hardness C-scale) and have a tissuecutting edge 176 formed on the distal end 174 thereof and be configuredto slidably extend through a slot in the anvil 20 and a centrallydisposed slot 33 in the staple cartridge 30 to cut through tissue thatis clamped in the end effector 12. In various embodiments, the knife rod180 extends through the spine member 50 and has a proximal end portionwhich drivingly interfaces with a knife transmission that is operablyattached to the knife advance trigger 200. In various embodiments, theknife advance trigger 200 is attached to pivot pin 132 such that it maybe pivoted or otherwise actuated without actuating the firing trigger130. In various embodiments, a first knife gear 192 is also attached tothe pivot pin 132 such that actuation of the knife advance trigger 200also pivots the first knife gear 192. A firing return spring 202 isattached between the first knife gear 192 and the handle housing 100 tobias the knife advancement trigger 200 to a starting or un-actuatedposition.

Various embodiments of the knife transmission also include a secondknife gear 194 that is rotatably supported on a second gear spindle andin meshing engagement with the first knife gear 192. The second knifegear 194 is in meshing engagement with a third knife gear 196 that issupported on a third gear spindle. Also supported on the third gearspindle 195 is a fourth knife gear 198. The fourth knife gear 198 isadapted to drivingly engage a series of annular gear teeth or rings on aproximal end of the knife rod 180. Thus, such arrangement enables thefourth knife gear 198 to axially drive the knife rod 180 in the distaldirection “DD” or proximal direction “PD” while enabling the firing rod180 to rotate about longitudinal axis A-A with respect to the fourthknife gear 198. Accordingly, the surgeon may axially advance the firingrod 180 and ultimately the knife member 172 distally by pulling theknife advancement trigger 200 towards the pistol grip 107 of the handleassembly 100.

Various embodiments of the present invention further include a knifelockout system 210 that prevents the advancement of the knife member 172unless the firing trigger 130 has been pulled to the fully firedposition. Such feature will therefore prevent the activation of theknife advancement system 170 unless the staples have first been fired orformed into the tissue. As can be seen in FIG. 1, variousimplementations of the knife lockout system 210 comprise a knife lockoutbar 211 that is pivotally supported within the pistol grip portion 107of the handle assembly 100. The knife lockout bar 211 has an activationend 212 that is adapted to be engaged by the firing trigger 130 when thefiring trigger 130 is in the fully fired position. In addition, theknife lockout bar 211 has a retaining hook 214 on its other end that isadapted to hookingly engage a latch rod 216 on the first cut gear 192. Aknife lock spring 218 is employed to bias the knife lockout bar 211 to a“locked” position wherein the retaining hook 214 is retained inengagement with the latch rod 216 to thereby prevent actuation of theknife advancement trigger 200 unless the firing trigger 130 is in thefully fired position.

After the staples have been “fired” (formed) into the target tissue, thesurgeon may depress the firing trigger release button 167 to enable thefiring trigger 130 to return to the starting position under the bias ofthe torsion spring 135 which enables the anvil 20 to be biased to anopen position under the bias of spring 21. When in the open position,the surgeon may withdraw the end effector 12 leaving the implantablestaple cartridge 30 and staples 32 behind. In applications wherein theend effector was inserted through a passage, working channel, etc. thesurgeon will return the anvil 20 to the closed position by activatingthe firing trigger 130 to enable the end effector 12 to be withdrawn outthrough the passage or working channel. If, however, the surgeon desiresto cut the target tissue after firing the staples, the surgeon activatesthe knife advancement trigger 200 in the above-described manner to drivethe knife bar 172 through the target tissue to the end of the endeffector. Thereafter, the surgeon may release the knife advancementtrigger 200 to enable the firing return spring 202 to cause the firingtransmission to return the knife bar 172 to the starting (un-actuated)position. Once the knife bar 172 has been returned to the startingposition, the surgeon may open the end effector jaws 13, 15 to releasethe implantable cartridge 30 within the patient and then withdraw theend effector 12 from the patient. Thus, such surgical instrumentsfacilitate the use of small implantable staple cartridges that may beinserted through relatively smaller working channels and passages, whileproviding the surgeon with the option to fire the staples withoutcutting tissue or if desired to also cut tissue after the staples havebeen fired.

Various unique and novel embodiments of the present invention employ acompressible staple cartridge that supports staples in a substantiallystationary position for forming contact by the anvil. In variousembodiments, the anvil is driven into the unformed staples wherein, inat least one such embodiment, the degree of staple formation attained isdependent upon how far the anvil is driven into the staples. Such anarrangement provides the surgeon with the ability to adjust the amountof forming or firing pressure applied to the staples and thereby alterthe final formed height of the staples. In other various embodiments ofthe present invention, surgical stapling arrangements can employ stapledriving elements which can lift the staples toward the anvil. Suchembodiments are described in greater detail further below.

In various embodiments, with regard to the embodiments described indetail above, the amount of firing motion that is applied to the movableanvil is dependent upon the degree of actuation of the firing trigger.For example, if the surgeon desires to attain only partially formedstaples, then the firing trigger is only partially depressed inwardtowards the pistol grip 107. To attain more staple formation, thesurgeon simply compresses the firing trigger further which results inthe anvil being further driven into forming contact with the staples. Asused herein, the term “forming contact” means that the staple formingsurface or staple forming pockets have contacted the ends of the staplelegs and have started to form or bend the legs over into a formedposition. The degree of staple formation refers to how far the staplelegs have been folded over and ultimately relates to the forming heightof the staple as referenced above. Those of ordinary skill in the artwill further understand that, because the anvil 20 moves in asubstantially parallel relationship with respect to the staple cartridgeas the firing motions are applied thereto, the staples are formedsubstantially simultaneously with substantially the same formed heights.

FIGS. 2 and 3 illustrate an alternative end effector 12″ that is similarto the end effector 12′ described above, except with the followingdifferences that are configured to accommodate a knife bar 172′. Theknife bar 172′ is coupled to or protrudes from a knife rod 180 and isotherwise operated in the above described manner with respect to theknife bar 172. However, in this embodiment, the knife bar 172′ is longenough to traverse the entire length of the end effector 12″ andtherefore, a separate distal knife member is not employed in the endeffector 12″. The knife bar 172′ has an upper transverse member 173′ anda lower transverse member 175′ formed thereon. The upper transversemember 173′ is oriented to slidably transverse a corresponding elongatedslot 250 in anvil 20″ and the lower transverse member 175′ is orientedto traverse an elongated slot 252 in the elongated channel 14″ of theend effector 12″. A disengagement slot (not shown) is also provide dinthe anvil 20″ such that when the knife bar 172′ has been driven to anending position with thin end effector 12″, the upper transverse member173′ drops through the corresponding slot to enable the anvil 20″ tomove to the open position to disengage the stapled and cut tissue. Theanvil 20″ may be otherwise identical to anvil 20 described above and theelongated channel 14″ may be otherwise identical to elongated channel 14described above.

In these embodiments, the anvil 20″ is biased to a fully open position(FIG. 2) by a spring or other opening arrangement (not shown). The anvil20″ is moved between the open and fully clamped positions by the axialtravel of the firing adapter 150 in the manner described above. Once thefiring adapter 150 has been advanced to the fully clamped position (FIG.3), the surgeon may then advance the knife bar 172″ distally in themanner described above. If the surgeon desires to use the end effectoras a grasping device to manipulate tissue, the firing adapter may bemoved proximally to allow the anvil 20″ to move away from the elongatedchannel 14″ as represented in FIG. 4 in broken lines. In thisembodiment, as the knife bar 172″ moves distally, the upper transversemember 173′ and the lower transverse member 175′ draw the anvil 20″ andelongated channel 14″ together to achieve the desired staple formationas the knife bar 172″ is advanced distally through the end effector 12″.See FIG. 5. Thus, in this embodiment, staple formation occurssimultaneously with tissue cutting, but the staples themselves may besequentially formed as the knife bar 172″ is driven distally.

The unique and novel features of the various surgical staple cartridgesand the surgical instruments of the present invention enable the staplesin those cartridges to be arranged in one or more linear or non-linearlines. A plurality of such staple lines may be provided on each side ofan elongated slot that is centrally disposed within the staple cartridgefor receiving the tissue cutting member therethrough. In onearrangement, for example, the staples in one line may be substantiallyparallel with the staples in adjacent line(s) of staples, but offsettherefrom. In still other embodiments, one or more lines of staples maybe non-linear in nature. That is, the base of at least one staple in aline of staples may extend along an axis that is substantiallytransverse to the bases of other staples in the same staple line. Forexample, as will be discussed in further detail below, in alternativeembodiments, the lines of staples on each side of the elongated slot mayhave a zigzag appearance. Such non-linear staple arrangements may attainbetter tissue fastening results with less staples than various linearstaple arrangements employed in prior staple cartridges.

FIG. 6 illustrates use of a surgical staple cartridge embodiment 900 inan end effector embodiment 612′. As can be seen in FIGS. 6 and 7, anembodiment of the surgical staple cartridge 900 has a cartridge body 902that has a centrally disposed elongated slot 904 extending through aproximal end 903 to an area adjacent a distal end 905. The elongatedslot 904 is configured to permit a knife body to axially movetherethrough during a tissue cutting operation in the manner describedabove. In at least one embodiment, the cartridge body 902 consists of acompressible hemostat material such as, for example, oxidizedregenerated cellulose (“ORC”) or a bio-absorbable foam fabricated from,for example, PGA (Polyglycolic acid, sold under the trademark Vicryl),PCL (polycaprolactone), PLA or PLLA (Polyactic acid), PDS,(Polydioxanone), PHA (polyhydroxyalkanoate), PGCL (poliglecaprone 25,sold under the trademark Monocryl) or a composite of PGA, PCL, PLA andPDS in which lines 920, 930 of unformed staples 922 are supported.However, the cartridge body 902 may be fabricated from other materialsthat serve to support the unformed staples 922 in a desired orientationsuch that they may be compressed as the anvil 910′ is brought intocontact therewith. As with various other embodiments described above,the staple cartridge 900 is implantable and is left attached to thestapled tissue after the stapling procedure has been completed. In atleast some embodiments, in order to prevent the staples 922 from beingaffected and the hemostat material from being activated during theintroduction and positioning process, the entire cartridge 900 may becoated or wrapped in a biodegradable film 906 such as a polydioxanonfilm sold under the trademark PDS® or with a Polyglycerol sebacate (PGS)film or other biodegradable films fabricated from, for example, PGA(Polyglycolic acid, marketed under the trade mark Vicryl), PCL(Polycaprolactone), PLA or PLLA (Polylactic acid), PHA(polyhydroxyalkanoate), PGCL (poliglecaprone 25, sold under thetrademark Monocryl) or a composite of PGA, PCL, PLA, PDS that would beimpermeable until ruptured. The cartridge body 902 of staple cartridge900 is sized to be removably supported within the elongated channel ofthe end effector 612′.

In the embodiment depicted in FIGS. 6, 10, and 11, the surgical staplecartridge 900 operably supports a first line 920 of staples 922 on onelateral side 907 of the elongated slot 904 and a second line 930 ofstaples 922 on the other lateral side 909 of the elongated slot 904. Invarious embodiments, the staples 922 may be fabricated from a metalmaterial such as, for example, Titanium, Titanium alloys (e.g., 6AI-4VTitanium, 3al-2.5V Titanium), Stainless Steel, etc. and have a staplebase 924 and two upstanding staple legs 926 protruding therefrom. Eachstaple leg 926 may have a tissue-piercing tip 928 formed thereon. In thefirst line 920 of staples 922, the staple base 924 of at least onestaple 922 overlaps the staple base of another staple 922. In apreferred embodiment, the staple base 924 of each staple 922 overlapsthe staple bases 924 of two adjacent staples 922, except for the base924 of the last staple 922 on each end of the first staple line 920. SeeFIG. 10. Thus, the first staple line 920 has a substantially non-linearshape. More particularly, when viewed from above, the first staple line920 has a substantially zigzag appearance.

As can be seen in FIG. 9, the anvil 90 has two sequential longitudinalstaple forming pockets 912 that each has a substantial zigzag shape thatcorresponds to the shape of the first line 920 of staples 922 such that,when the anvil 910 is brought into forming contact with the staples 922,the legs 926 thereof are formed as shown in FIG. 11. Thus, the distalleg of one staple shares the same pocket as the proximal leg of the nextstaple longitudinally. Such arrangement allows for a denser pocketpattern, even to a point where the staples themselves interact (e.g.,are folded over one another). In prior staple pocket arrangements, ingeneral, there has to be between 0.005 and 0.015 inches of metal/spacefrom one set of pockets to the next. This embodiment of the presentinvention, however, has a spacing arrangement from 0 to 0.02 inches ofinterference/overlap (essentially a −0.020″) because one staple mateswith the next staple, for example. Such arrangements allow for 15-30%more staples in the same space. Furthermore, when the staples interlock,there is less need for multiple lateral rows of staples. Priorarrangements commonly employ three rows on each side of the tissue cutline to prevent the existing of an open path through which blood maypass. Lines of interlocking staples are less likely to leave pathsthrough which blood may pass. Another distinct advantage provided by thevarious interlocking staple arrangements of the present inventionrelates to improved “burst strength” which relates to the amount offorce required to tear a staple line open.

Another staple forming pocket arrangement may comprise a common stapleforming pocket. As used herein, the term “common staple forming pocket”means that one forming pocket can form all of the staples in a singleline of staples as opposed to prior anvil designs wherein a discreteforming pocket is provided for each leg of each staple to be formed.

FIG. 12 illustrates yet another staple embodiment 922′ wherein the base924′ has an offset portion 929 to facilitate a tighter overlap of thebases 924′. As indicated above, the staple cartridge 900 has a secondline 930 of staples 922 supported on a second lateral side 909 of theelongated slot 904. The second line 930 of staples 922 is substantiallyidentical to the first line 920 of staples 922. Thus, the anvil 910 hasa second common staple forming pocket 912 that corresponds to the secondline of staples 930 for forming contact therewith. In alternativeembodiments, however, the second line 930 of staples 922 may differ fromthe first line 920 of staples in shape and, perhaps, number of staples.

FIG. 8 illustrates a surgical staple cartridge 900′ that issubstantially identical to the staple cartridge 900 described above,with the exception of the lines 920′, 930′ of staples 922 supportedtherein. For example, in this embodiment, the line 920′ of staples 922are arranged relative to each other such that a base axis S-S of atleast one staple base 924 is substantially transverse to the base axisS-S of the staple base 924 of at least one other adjacent staple 922.Such predetermined pattern of staples, when viewed from above, comprisesa substantially zigzag arrangement. In the embodiment depicted in FIG.13, the respective bases 924 of staples 922 may additionally have a basesupport member 927 overmolded thereon as shown. In various embodiments,the base support member 927 may be fabricated from, for example,non-absorbable plastic such as Polyether ether ketone “PEEK” orabsorbable plastic such as, for example, Polyglycolic acid “PGA”,Polylactic acid “PLA” or “PLLA”, Polydioxanone “PDS”, PCL(polycaprolactone), PHA (polyhydroxyalkanoate), PGCL (poliglecaprone 25,sold under the trademark Monocryl) or various composite mixes if PGS,PDS, PLA, PGA, and PCL. The base support members 927 facilitateinterlocking between the staples without making the staples themselvesoverlap. Thus, such arrangements could form staples with “B” shapes orinverted “W” shapes without the legs of the staples themselvesoverlapping. However, the crowns are connected by the base supportmembers so they act like overlaping staples. Such arrangements allow thecombined pockets to have two discrete paths for each leg.

The embodiment depicted in FIG. 14 employs a staple line 920″ whereinthe legs 926 of adjacent staples 922 are coupled together by a couplerportion 929 molded or otherwise attached thereto. Each coupler portion929 may be fabricated from, for example, Polyether ether ketone “PEEK”or absorbable plastic such as, for example, Polyglycolic acid “PGA”,Polylactic acid “PLA” or “PLLA”, Polydioxanone “PDS”, PCL(polycaprolactone), PHA (polyhydroxyalkanoate), PGCL (poliglecaprone 25,sold under the trademark Monocryl) or various composite mixes if PGS,PDS, PLA, PGA, and PCL. Such staple line 920″ has substantial zigzagappearance when viewed from above. While the various surgical staplecartridge embodiments 900, 900′ have been explained with reference touse with the end effector 612′, it will be understood that the staplecartridges 900, 900′ may be effectively employed with the various otherend effectors and surgical instruments described hereinabove, withappropriate staple forming pocket arrangements being provided in theanvils of those instruments in order to achieved the desired amount ofstaple formation upon movement of the anvils into forming contact withthe staples.

FIGS. 15 and 16 illustrate another surgical staple cartridge 940embodiment supported in an elongated channel 14 of a surgical instrument10. In at least one embodiment, the surgical staple cartridge 940includes a cartridge body 942 that has a centrally disposed elongatedslot 944 extending at least partially therethrough. The elongated slot944 is configured to permit a knife body of the surgical instrument 10to axially move therethrough during a tissue cutting operation in themanner described above. In various embodiments, the cartridge body 942consists of a compressible hemostat material such as, for example,oxidized regenerated cellulose (“ORC”) or a bio-absorbable foam of thetypes described above or below in which lines 946, 948, 950, 952 ofunformed staples 922 are supported. In at least some embodiments, inorder to prevent the staples 922 from being affected and the hemostatmaterial from being activated during the introduction and positioningprocess, the entire cartridge 940 may be coated or wrapped in abiodegradable film 954 such as a polydioxanon film sold under thetrademark PDS® or with a Polyglycerol sebacate (PGS) film or otherbiodegradable films fabricated from, for example, PGA (Polyglycolicacid, marketed under the trade mark Vicryl), PCL (Polycaprolactone), PLAor PLLA (Polylactic acid), PHA (polyhydroxyalkanoate), PGCL(poliglecaprone 25, sold under the trademark Monocryl) or a composite ofPGA, PCL, PLA, PDS that would be impermeable until ruptured.

In the embodiment depicted in FIG. 15, the cartridge 940 furtherincludes a cartridge support member 960 that is coupled to the cartridgebody 942. In various embodiments, the cartridge support member 960 maybe fabricated from a rigid material such as, for example, Titanium,Stainless Steel, Aluminum, any alloy of the foregoing, etc. and may bepartially embedded within the cartridge body 942. In variousembodiments, the cartridge support member 960 may be held in place by,for example, film 954. In still other embodiments wherein a limited bondis desired, sporadic use of cyanoacylate could be used to “glue” the twocomponents together. In yet other embodiments, the cartridge body 942may be heated and “welded” or “fused” to the cartridge support member960. In various embodiments, the cartridge support member 960 forms atleast a portion of the bottom surface of the cartridge body 942 formating with the elongated channel 14. In at least one embodiment, thecartridge support member 960 has one or more snap features 962protruding therefrom for releasably coupling the cartridge supportmember 960 to the elongated channel 14. Other forms of snapfeatures/fastener arrangements may be employed for releasably couplingthe cartridge support member 960 to the elongated channel 14.

In various embodiments, the cartridge support member 960 has a series ofsupport ridges 964, 966, 968, 970, 972, 974, 976 formed thereon toprovide some lateral support to the bases 924 of the staples 922 in thestaple lines 946, 948, 950, 952 as shown in FIG. 15. Thus, in at leastsome embodiments, the support ridges are substantially coextensive withthe staple lines. FIG. 17 illustrates an alternative staple cartridgeembodiment 940′ that is substantially identical to cartridge 940, exceptfor the inclusion of upstanding fin portions 978, 979, 980, 981, 982,983 that protrude from the support ridges 964, 966, 968, 970, 972, 976,respectively to provide additional lateral support to the staples 922.In various embodiments, the fin portions may be integrally formed withthe cartridge support member 960 and have a height that is about ½ orless of the height of the cartridge. Thus, in various embodiments, forexample, any standing features supporting the foam cannot extend abovethe maximum compression height of the foam. Thus, if the cartridge isdesigned, for example, to compress to ⅓ of its original height whenfired, the fins would between 66% of the uncompressed height, all theway down to 10% of uncompressed height.

In use, once the staples 922 have been formed through contact with theanvil 20 in the manner described above, the anvil 20 is opened and theend effector 12 is pulled away from the stapled tissue. As the endeffector 12 is pulled away from the stapled tissue, the cartridge body942 remains fastened to the stapled tissue and is then separated fromthe cartridge support member 960 which remains coupled to the elongatedchannel 14. In various embodiments, the cartridge support member 960 isprovided with a color that differs from the color of the materialcomprising the cartridge body 942 as well as the color of the elongatedchannel 14. Such arrangement provides the surgeon with an easilyrecognizable indication that no staple cartridge is present within theend effector. Thus, the surgeon will not inadvertently attempt toreinsert/use the end effector without first installing a new staplecartridge therein. To do so, the surgeon simply disconnects the snapfeatures of the cartridge support member 960 from the elongated channel14 to enable the cartridge support member 960 of a new staple cartridge940 to be placed therein. While the staple cartridges 940, 940′ havebeen explained with reference to surgical instrument 10, it will beunderstood that those cartridges may be effectively employed with manyof the other surgical instrument embodiments disclosed herein withoutdeparting from the spirit and scope of the present invention.

In various embodiments, a staple cartridge can comprise a cartridge bodyand a plurality of staples stored within the cartridge body. In use, thestaple cartridge can be introduced into a surgical site and positionedon a side of the tissue being treated. In addition, a staple-forminganvil can be positioned on the opposite side of the tissue. In variousembodiments, the anvil can be carried by a first jaw and the staplecartridge can be carried by a second jaw, wherein the first jaw and/orthe second jaw can be moved toward the other. Once the staple cartridgeand the anvil have been positioned relative to the tissue, the staplescan be ejected from the staple cartridge body such that the staples canpierce the tissue and contact the staple-forming anvil. Once the stapleshave been deployed from the staple cartridge body, the staple cartridgebody can then be removed from the surgical site. In various embodimentsdisclosed herein, a staple cartridge, or at least a portion of a staplecartridge, can be implanted with the staples. In at least one suchembodiment, as described in greater detail further below, a staplecartridge can comprise a cartridge body which can be compressed,crushed, and/or collapsed by the anvil when the anvil is moved from anopen position into a closed position. When the cartridge body iscompressed, crushed, and/or collapsed, the staples positioned within thecartridge body can be deformed by the anvil. Alternatively, the jawsupporting the staple cartridge can be moved toward the anvil into aclosed position. In either event, in various embodiments, the staplescan be deformed while they are at least partially positioned within thecartridge body. In certain embodiments, the staples may not be ejectedfrom the staple cartridge while, in some embodiments, the staples can beejected from the staple cartridge along with a portion of the cartridgebody.

Referring now to FIGS. 18A-18D, a compressible staple cartridge, such asstaple cartridge 1000, for example, can comprise a compressible,implantable cartridge body 1010 and, in addition, a plurality of staples1020 positioned in the compressible cartridge body 1010, although onlyone staple 1020 is depicted in FIGS. 18A-18D. FIG. 18A illustrates thestaple cartridge 1000 supported by a staple cartridge support, or staplecartridge channel, 1030, wherein the staple cartridge 1000 isillustrated in an uncompressed condition. In such an uncompressedcondition, the anvil 1040 may or may not be in contact with the tissueT. In use, the anvil 1040 can be moved from an open position intocontact with the tissue T as illustrated in FIG. 18B and position thetissue T against the cartridge body 1010. Even though the anvil 1040 canposition the tissue T against a tissue-contacting surface 1019 of staplecartridge body 1010, referring again to FIG. 18B, the staple cartridgebody 1010 may be subjected to little, if any, compressive force orpressure at such point and the staples 1020 may remain in an unformed,or unfired, condition. As illustrated in FIGS. 18A and 18B, the staplecartridge body 1010 can comprise one or more layers and the staple legs1021 of staples 1020 can extend upwardly through these layers. Invarious embodiments, the cartridge body 1010 can comprise a first layer1011, a second layer 1012, a third layer 1013, wherein the second layer1012 can be positioned intermediate the first layer 1011 and the thirdlayer 1013, and a fourth layer 1014, wherein the third layer 1013 can bepositioned intermediate the second layer 1012 and the fourth layer 1014.In at least one embodiment, the bases 1022 of the staples 1020 can bepositioned within cavities 1015 in the fourth layer 1014 and the staplelegs 1021 can extend upwardly from the bases 1022 and through the fourthlayer 1014, the third layer 1013, and the second layer 1012, forexample. In various embodiments, each deformable leg 1021 can comprise atip, such as sharp tip 1023, for example, which can be positioned in thesecond layer 1012, for example, when the staple cartridge 1000 is in anuncompressed condition. In at least one such embodiment, the tips 1023may not extend into and/or through the first layer 1011, wherein, in atleast one embodiment, the tips 1023 may not protrude through thetissue-contacting surface 1019 when the staple cartridge 1000 is in anuncompressed condition. In certain other embodiments, the sharp tips1023 may be positioned in the third layer 1013, and/or any othersuitable layer, when the staple cartridge is in an uncompressedcondition. In various alternative embodiments, a cartridge body of astaple cartridge may have any suitable number of layers such as lessthan four layers or more than four layers, for example.

In various embodiments, as described in greater detail below, the firstlayer 1011 can be comprised of a buttress material and/or plasticmaterial, such as polydioxanone (PDS) and/or polyglycolic acid (PGA),for example, and the second layer 1012 can be comprised of abioabsorbable foam material and/or a compressible hemostatic material,such as oxidized regenerated cellulose (ORC), for example. In variousembodiments, one or more of the first layer 1011, the second layer 1012,the third layer 1013, and the fourth layer 1014 may hold the staples1020 within the staple cartridge body 1010 and, in addition, maintainthe staples 1020 in alignment with one another. In various embodiments,the third layer 1013 can be comprised of a buttress material, or afairly incompressible or inelastic material, which can be configured tohold the staple legs 1021 of the staples 1020 in position relative toone another. Furthermore, the second layer 1012 and the fourth layer1014, which are positioned on opposite sides of the third layer 1013,can stabilize, or reduce the movement of, the staples 1020 even thoughthe second layer 1012 and the fourth layer 1014 can be comprised of acompressible foam or elastic material. In certain embodiments, thestaple tips 1023 of the staple legs 1021 can be at least partiallyembedded in the first layer 1011. In at least one such embodiment, thefirst layer 1011 and the third layer 1013 can be configured toco-operatively and firmly hold the staple legs 1021 in position. In atleast one embodiment, the first layer 1011 and the third layer 1013 caneach be comprised of a sheet of bioabsorbable plastic, such aspolyglycolic acid (PGA) which is marketed under the trade name Vicryl,polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate(PHA), poliglecaprone 25 (PGCL) which is marketed under the trade nameMonocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS,PHA, PGCL and/or PCL, for example, and the second layer 1012 and thefourth layer 1014 can each be comprised of at least one hemostaticmaterial or agent.

Although the first layer 1011 can be compressible, the second layer 1012can be substantially more compressible than the first layer 1011. Forexample, the second layer 1012 can be about twice as compressible, aboutthree times as compressible, about four times as compressible, aboutfive times as compressible, and/or about ten times as compressible, forexample, as the first layer 1011. Stated another way, the second layer1012 may compress about two times, about three times, about four times,about five times, and/or about ten times as much as first layer 1011,for a given force. In certain embodiments, the second layer 1012 can bebetween about twice as compressible and about ten times as compressible,for example, as the first layer 1011. In at least one embodiment, thesecond layer 1012 can comprise a plurality of air voids defined therein,wherein the amount and/or size of the air voids in the second layer 1012can be controlled in order to provide a desired compressibility of thesecond layer 1012. Similar to the above, although the third layer 1013can be compressible, the fourth layer 1014 can be substantially morecompressible than the third layer 1013. For example, the fourth layer1014 can be about twice as compressible, about three times ascompressible, about four times as compressible, about five times ascompressible, and/or about ten times as compressible, for example, asthe third layer 1013. Stated another way, the fourth layer 1014 maycompress about two times, about three times, about four times, aboutfive times, and/or about ten times as much as third layer 1013, for agiven force. In certain embodiments, the fourth layer 1014 can bebetween about twice as compressible and about ten times as compressible,for example, as the third layer 1013. In at least one embodiment, thefourth layer 1014 can comprise a plurality of air voids defined therein,wherein the amount and/or size of the air voids in the fourth layer 1014can be controlled in order to provide a desired compressibility of thefourth layer 1014. In various circumstances, the compressibility of acartridge body, or cartridge body layer, can be expressed in terms of acompression rate, i.e., a distance in which a layer is compressed for agiven amount of force. For example, a layer having a high compressionrate will compress a larger distance for a given amount of compressiveforce applied to the layer as compared to a layer having a lowercompression rate. This being said, the second layer 1012 can have ahigher compression rate than the first layer 1011 and, similarly, thefourth layer 1014 can have a higher compression rate than the thirdlayer 1013. In various embodiments, the second layer 1012 and the fourthlayer 1014 can be comprised of the same material and can comprise thesame compression rate. In various embodiments, the second layer 1012 andthe fourth layer 1014 can be comprised of materials having differentcompression rates. Similarly, the first layer 1011 and the third layer1013 can be comprised of the same material and can comprise the samecompression rate. In certain embodiments, the first layer 1011 and thethird layer 1013 can be comprised of materials having differentcompression rates.

As the anvil 1040 is moved toward its closed position, the anvil 1040can contact tissue T and apply a compressive force to the tissue T andthe staple cartridge 1000, as illustrated in FIG. 18C. In suchcircumstances, the anvil 1040 can push the top surface, ortissue-contacting surface 1019, of the cartridge body 1010 downwardlytoward the staple cartridge support 1030. In various embodiments, thestaple cartridge support 1030 can comprise a cartridge support surface1031 which can be configured to support the staple cartridge 1000 as thestaple cartridge 1000 is compressed between the cartridge supportsurface 1031 and the tissue-contacting surface 1041 of anvil 1040. Owingto the pressure applied by the anvil 1040, the cartridge body 1010 canbe compressed and the anvil 1040 can come into contact with the staples1020. More particularly, in various embodiments, the compression of thecartridge body 1010 and the downward movement of the tissue-contactingsurface 1019 can cause the tips 1023 of the staple legs 1021 to piercethe first layer 1011 of cartridge body 1010, pierce the tissue T, andenter into forming pockets 1042 in the anvil 1040. As the cartridge body1010 is further compressed by the anvil 1040, the tips 1023 can contactthe walls defining the forming pockets 1042 and, as a result, the legs1021 can be deformed or curled inwardly, for example, as illustrated inFIG. 18C. As the staple legs 1021 are being deformed, as alsoillustrated in FIG. 18C, the bases 1022 of the staples 1020 can be incontact with or supported by the staple cartridge support 1030. Invarious embodiments, as described in greater detail below, the staplecartridge support 1030 can comprise a plurality of support features,such as staple support grooves, slots, or troughs 1032, for example,which can be configured to support the staples 1020, or at least thebases 1022 of the staples 1020, as the staples 1020 are being deformed.As also illustrated in FIG. 18C, the cavities 1015 in the fourth layer1014 can collapse as a result of the compressive force applied to thestaple cartridge body 1010. In addition to the cavities 1015, the staplecartridge body 1010 can further comprise one or more voids, such asvoids 1016, for example, which may or may not comprise a portion of astaple positioned therein, that can be configured to allow the cartridgebody 1010 to collapse. In various embodiments, the cavities 1015 and/orthe voids 1016 can be configured to collapse such that the wallsdefining the cavities and/or walls deflect downwardly and contact thecartridge support surface 1031 and/or contact a layer of the cartridgebody 1010 positioned underneath the cavities and/or voids.

Upon comparing FIG. 18B and FIG. 18C, it is evident that the secondlayer 1012 and the fourth layer 1014 have been substantially compressedby the compressive pressure applied by the anvil 1040. It may also benoted that the first layer 1011 and the third layer 1013 have beencompressed as well. As the anvil 1040 is moved into its closed position,the anvil 1040 may continue to further compress the cartridge body 1010by pushing the tissue-contacting surface 1019 downwardly toward thestaple cartridge support 1030. As the cartridge body 1010 is furthercompressed, the anvil 1040 can deform the staples 1020 into theircompletely-formed shape as illustrated in FIG. 18D. Referring to FIG.18D, the legs 1021 of each staple 1020 can be deformed downwardly towardthe base 1022 of each staple 1020 in order to capture at least a portionof the tissue T, the first layer 1011, the second layer 1012, the thirdlayer 1013, and the fourth layer 1014 between the deformable legs 1021and the base 1022. Upon comparing FIGS. 18C and 18D, it is furtherevident that the second layer 1012 and the fourth layer 1014 have beenfurther substantially compressed by the compressive pressure applied bythe anvil 1040. It may also be noted upon comparing FIGS. 18C and 18Dthat the first layer 1011 and the third layer 1013 have been furthercompressed as well. After the staples 1020 have been completely, or atleast sufficiently, formed, the anvil 1040 can be lifted away from thetissue T and the staple cartridge support 1030 can be moved away, and/ordetached from, the staple cartridge 1000. As depicted in FIG. 18D, andas a result of the above, the cartridge body 1010 can be implanted withthe staples 1020. In various circumstances, the implanted cartridge body1010 can support the tissue along the staple line. In somecircumstances, a hemostatic agent, and/or any other suitable therapeuticmedicament, contained within the implanted cartridge body 1010 can treatthe tissue over time. A hemostatic agent, as mentioned above, can reducethe bleeding of the stapled and/or incised tissue while a bonding agentor tissue adhesive can provide strength to the tissue over time. Theimplanted cartridge body 1010 can be comprised of materials such as ORC(oxidized regenerated cellulous), protein matrix, polyglycolic acid(PGA) which is marketed under the trade name Vicryl, polylactic acid(PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA),poliglecaprone 25 (PGCL) which is marketed under the trade nameMonocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS,PHA, PGCL and/or PCL, for example. In certain circumstances, thecartridge body 1010 can comprise an antibiotic and/or anti-microbialmaterial, such as colloidal silver and/or triclosan, for example, whichcan reduce the possibility of infection in the surgical site.

In various embodiments, the layers of the cartridge body 1010 can beconnected to one another. In at least one embodiment, the second layer1012 can be adhered to the first layer 1011, the third layer 1013 can beadhered to the second layer 1012, and the fourth layer 1014 can beadhered to the third layer 1013 utilizing at least one adhesive, such asfibrin and/or protein hydrogel, for example. In certain embodiments,although not illustrated, the layers of the cartridge body 1010 can beconnected together by interlocking mechanical features. In at least onesuch embodiment, the first layer 1011 and the second layer 1012 can eachcomprise corresponding interlocking features, such as a tongue andgroove arrangement and/or a dovetail joint arrangement, for example.Similarly, the second layer 1012 and the third layer 1013 can eachcomprise corresponding interlocking features while the third layer 1013and the fourth layer 1014 can each comprise corresponding interlockingfeatures. In certain embodiments, although not illustrated, the staplecartridge 1000 can comprise one or more rivets, for example, which canextend through one or more layers of the cartridge body 1010. In atleast one such embodiment, each rivet can comprise a first end, or head,positioned adjacent to the first layer 1011 and a second head positionedadjacent to the fourth layer 1014 which can be either assembled to orformed by a second end of the rivet. Owing to the compressible nature ofthe cartridge body 1010, in at least one embodiment, the rivets cancompress the cartridge body 1010 such that the heads of the rivets canbe recessed relative to the tissue-contacting surface 1019 and/or thebottom surface 1018 of the cartridge body 1010, for example. In at leastone such embodiment, the rivets can be comprised of a bioabsorbablematerial, such as polyglycolic acid (PGA) which is marketed under thetrade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS),polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketedunder the trade name Monocryl, polycaprolactone (PCL), and/or acomposite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. Incertain embodiments, the layers of the cartridge body 1010 may not beconnected to one another other than by the staples 1020 containedtherein. In at least one such embodiment, the frictional engagementbetween the staple legs 1021 and the cartridge body 1010, for example,can hold the layers of the cartridge body 1010 together and, once thestaples have been formed, the layers can be captured within the staples1020. In certain embodiments, at least a portion of the staple legs 1021can comprise a roughened surface or rough coating which can increase thefriction forces between the staples 1020 and the cartridge body 1010.

As described above, a surgical instrument can comprise a first jawincluding the staple cartridge support 1030 and a second jaw includingthe anvil 1040. In various embodiments, as described in greater detailfurther below, the staple cartridge 1000 can comprise one or moreretention features which can be configured to engage the staplecartridge support 1030 and, as a result, releasably retain the staplecartridge 1000 to the staple cartridge support 1030. In certainembodiments, the staple cartridge 1000 can be adhered to the staplecartridge support 1030 by at least one adhesive, such as fibrin and/orprotein hydrogel, for example. In use, in at least one circumstance,especially in laparoscopic and/or endoscopic surgery, the second jaw canbe moved into a closed position opposite the first jaw, for example,such that the first and second jaws can be inserted through a trocarinto a surgical site. In at least one such embodiment, the trocar candefine an approximately 5 mm aperture, or cannula, through which thefirst and second jaws can be inserted. In certain embodiments, thesecond jaw can be moved into a partially-closed position intermediatethe open position and the closed position which can allow the first andsecond jaws to be inserted through the trocar without deforming thestaples 1020 contained in the staple cartridge body 1010. In at leastone such embodiment, the anvil 1040 may not apply a compressive force tothe staple cartridge body 1010 when the second jaw is in itspartially-closed intermediate position while, in certain otherembodiments, the anvil 1040 can compress the staple cartridge body 1010when the second jaw is in its partially-closed intermediate position.Even though the anvil 1040 can compress the staple cartridge body 1010when it is in such an intermediate position, the anvil 1040 may notsufficiently compress the staple cartridge body 1010 such that the anvil1040 comes into contact with the staples 1020 and/or such that thestaples 1020 are deformed by the anvil 1040. Once the first and secondjaws have been inserted through the trocar into the surgical site, thesecond jaw can be opened once again and the anvil 1040 and the staplecartridge 1000 can be positioned relative to the targeted tissue asdescribed above.

In various embodiments, referring now to FIGS. 19A-19D, an end effectorof a surgical stapler can comprise an implantable staple cartridge 1100positioned intermediate an anvil 1140 and a staple cartridge support1130. Similar to the above, the anvil 1140 can comprise atissue-contacting surface 1141, the staple cartridge 1100 can comprise atissue-contacting surface 1119, and the staple cartridge support 1130can comprise a support surface 1131 which can be configured to supportthe staple cartridge 1100. Referring to FIG. 19A, the anvil 1140 can beutilized to position the tissue T against the tissue contacting surface1119 of staple cartridge 1100 without deforming the staple cartridge1100 and, when the anvil 1140 is in such a position, thetissue-contacting surface 1141 can be positioned a distance 1101 a awayfrom the staple cartridge support surface 1131 and the tissue-contactingsurface 1119 can be positioned a distance 1102 a away from the staplecartridge support surface 1131. Thereafter, as the anvil 1140 is movedtoward the staple cartridge support 1130, referring now to FIG. 19B, theanvil 1140 can push the top surface, or tissue-contacting surface 1119,of staple cartridge 1100 downwardly and compress the first layer 1111and the second layer 1112 of cartridge body 1110. As the layers 1111 and1112 are compressed, referring again to FIG. 19B, the second layer 1112can be crushed and the legs 1121 of staples 1120 can pierce the firstlayer 1111 and enter into the tissue T. In at least one such embodiment,the staples 1120 can be at least partially positioned within staplecavities, or voids, 1115 in the second layer 1112 and, when the secondlayer 1112 is compressed, the staple cavities 1115 can collapse and, asa result, allow the second layer 1112 to collapse around the staples1120. In various embodiments, the second layer 1112 can comprise coverportions 1116 which can extend over the staple cavities 1115 andenclose, or at least partially enclose, the staple cavities 1115. FIG.19B illustrates the cover portions 1116 being crushed downwardly intothe staple cavities 1115. In certain embodiments, the second layer 1112can comprise one or more weakened portions which can facilitate thecollapse of the second layer 1112. In various embodiments, such weakenedportions can comprise score marks, perforations, and/or thincross-sections, for example, which can facilitate a controlled collapseof the cartridge body 1110. In at least one embodiment, the first layer1111 can comprise one or more weakened portions which can facilitate thepenetration of the staple legs 1121 through the first layer 1111. Invarious embodiments, such weakened portions can comprise score marks,perforations, and/or thin cross-sections, for example, which can bealigned, or at least substantially aligned, with the staple legs 1121.

When the anvil 1140 is in a partially closed, unfired position,referring again to FIG. 19A, the anvil 1140 can be positioned a distance1101 a away from the cartridge support surface 1131 such that a gap isdefined therebetween. This gap can be filled by the staple cartridge1100, having a staple cartridge height 1102 a, and the tissue T. As theanvil 1140 is moved downwardly to compress the staple cartridge 1100,referring again to FIG. 19B, the distance between the tissue contactingsurface 1141 and the cartridge support surface 1131 can be defined by adistance 1101 b which is shorter than the distance 1101 a. In variouscircumstances, the gap between the tissue-contacting surface 1141 ofanvil 1140 and the cartridge support surface 1131, defined by distance1101 b, may be larger than the original, undeformed staple cartridgeheight 1102 a. As the anvil 1140 is moved closer to the cartridgesupport surface 1131, referring now to FIG. 19C, the second layer 1112can continue to collapse and the distance between the staple legs 1121and the forming pockets 1142 can decrease. Similarly, the distancebetween the tissue-contacting surface 1141 and the cartridge supportsurface 1131 can decrease to a distance 1101 c which, in variousembodiments, may be greater than, equal to, or less than the original,undeformed cartridge height 1102 a. Referring now to FIG. 19D, the anvil1140 can be moved into a final, fired position in which the staples 1120have been fully formed, or at least formed to a desired height. In sucha position, the tissue-contacting surface 1141 of anvil 1140 can be adistance 1101 d away from the cartridge support surface 1131, whereinthe distance 1101 d can be shorter than the original, undeformedcartridge height 1102 a. As also illustrated in FIG. 19D, the staplecavities 1115 may be fully, or at least substantially, collapsed and thestaples 1120 may be completely, or at least substantially, surrounded bythe collapsed second layer 1112. In various circumstances, the anvil1140 can be thereafter moved away from the staple cartridge 1100. Oncethe anvil 1140 has been disengaged from the staple cartridge 1100, thecartridge body 1110 can at least partially re-expand in variouslocations, i.e., locations intermediate adjacent staples 1120, forexample. In at least one embodiment, the crushed cartridge body 1110 maynot resiliently re-expand. In various embodiments, the formed staples1120 and, in addition, the cartridge body 1110 positioned intermediateadjacent staples 1120 may apply pressure, or compressive forces, to thetissue T which may provide various therapeutic benefits.

As discussed above, referring again to the embodiment illustrated inFIG. 19A, each staple 1120 can comprise staple legs 1121 extendingtherefrom. Although staples 1120 are depicted as comprising two staplelegs 1121, various staples can be utilized which can comprise one stapleleg or, alternatively, more than two staple legs, such as three staplelegs or four staple legs, for example. As illustrated in FIG. 19A, eachstaple leg 1121 can be embedded in the second layer 1112 of thecartridge body 1110 such that the staples 1120 are secured within thesecond layer 1112. In various embodiments, the staples 1120 can beinserted into the staple cavities 1115 in cartridge body 1110 such thatthe tips 1123 of the staple legs 1121 enter into the cavities 1115before the bases 1122. After the tips 1123 have been inserted into thecavities 1115, in various embodiments, the tips 1123 can be pressed intothe cover portions 1116 and incise the second layer 1112. In variousembodiments, the staples 1120 can be seated to a sufficient depth withinthe second layer 1112 such that the staples 1120 do not move, or atleast substantially move, relative to the second layer 1112. In certainembodiments, the staples 1120 can be seated to a sufficient depth withinthe second layer 1112 such that the bases 1122 are positioned orembedded within the staple cavities 1115. In various other embodiments,the bases 1122 may not be positioned or embedded within the second layer1112. In certain embodiments, referring again to FIG. 19A, the bases1122 may extend below the bottom surface 1118 of the cartridge body1110. In certain embodiments, the bases 1122 can rest on, or can bedirectly positioned against, the cartridge support surface 1130. Invarious embodiments, the cartridge support surface 1130 can comprisesupport features extending therefrom and/or defined therein wherein, inat least one such embodiment, the bases 1122 of the staples 1120 may bepositioned within and supported by one or more support grooves, slots,or troughs, 1132, for example, in the staple cartridge support 1130, asdescribed in greater detail further below.

Further to the above, referring now to FIG. 20, the bases 1122 of thestaples 1120 can be positioned directly against the support surface 1131of staple cartridge support 1130. In various embodiments, includingembodiments where the staple bases 1122 comprise circular or arcuatebottom surfaces 1124, for example, the staple bases 1122 may move orslide along the staple cartridge support surface 1131. Such sliding canoccur when the anvil 1140 is pressed against the tips 1123 of the staplelegs 1121 during the staple forming process. In certain embodiments, asdescribed above and referring now to FIG. 21, the staple cartridgesupport 1130 can comprise one or more support slots 1132 therein whichcan be configured to eliminate, or at least reduce, the relativemovement between the staple bases 1122 and the cartridge support surface1131. In at least one such embodiment, each support slot 1132 can bedefined by a surface contour which matches, or at least substantiallymatches, the contour of the bottom surface of the staple positionedtherein. For example, the bottom surface 1124 of the base 1122 depictedin FIG. 21 can comprise a circular, or at least substantially circular,surface and the support slot 1132 can also comprise a circular, or atleast substantially circular, surface. In at least one such embodiment,the surface defining the slot 1132 can be defined by a radius ofcurvature which is greater than or equal to a radius of curvature whichdefines bottom surface 1124. Although the slots 1132 may assist inpreventing or reducing relative sliding movement between the staples1120 and the staple cartridge support 1130, the slots 1132 may also beconfigured to prevent or reduce relative rotational movement between thestaples 1120 and the staple cartridge support 1130. More particularly,in at least one embodiment, the slots 1132 can be configured to closelyreceive the bases 1122 in order to prevent or reduce the rotation of thestaples 1120 about axes 1129, for example, such that the staples 1120 donot rotate or twist when they are being deformed.

In various embodiments, further to the above, each staple 1120 can beformed from a round, or an at least substantially round, wire. Incertain embodiments, the legs and the base of each staple can be formedfrom a wire having a non-circular cross-section, such as a rectangularcross-section, for example. In at least one such embodiment, the staplecartridge support 1130 can comprise corresponding non-circular slots,such as rectangular slots, for example, configured to receive the basesof such staples. In various embodiments, referring now to FIG. 22, eachstaple 1120 can comprise a crown, such as a crown 1125, for example,overmolded onto a base 1122 wherein each crown 1125 can be positionedwithin a support slot in the staple cartridge support 1130. In at leastone such embodiment, each crown 1125 can comprise a square and/orrectangular cross-section, for example, which can be configured to bereceived within square and/or rectangular slots 1134, for example, inthe staple cartridge support 1130. In various embodiments, the crowns1125 can be comprised of a bioabsorbable plastic, such as polyglycolicacid (PGA) which is marketed under the trade name Vicryl, polylacticacid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA),poliglecaprone 25 (PGCL) which is marketed under the trade nameMonocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS,PHA, PGCL and/or PCL, for example, and can be formed around the bases1122 of the staples 1120 by an injection molding process, for example.Various crowns and methods for forming various crowns are disclosed inU.S. patent application Ser. No. 11/541,123, entitled SURGICAL STAPLESHAVING COMPRESSIBLE OR CRUSHABLE MEMBERS FOR SECURING TISSUE THEREIN ANDSTAPLING INSTRUMENTS FOR DEPLOYING THE SAME, filed on Sep. 29, 2006, theentire disclosure of which is incorporated be reference herein.Referring again to FIG. 22, the slots 1134 can further compriselead-ins, or bevels, 1135 which can be configured to facilitate theinsertion of the crowns 1125 into the slots 1134. In variousembodiments, the bases and/or crowns of the staples 1120 may bepositioned within the slots 1134 when the staple cartridge 1100 isassembled to the staple cartridge support 1130. In certain embodiments,the crowns 1125 of the staples 1120 may be aligned with the slots 1134when the staple cartridge 1100 is assembled to the staple cartridgesupport 1130. In at least one such embodiment, the crowns 1125 may notenter into the slots 1134 until a compressive force is applied to thestaple legs 1121 and the bases and/or crowns of the staples 1120 arepushed downwardly into the slots 1134.

In various embodiments, referring now to FIGS. 23 and 24, a staplecartridge, such as staple cartridge 1200, for example, can comprise acompressible, implantable cartridge body 1210 comprising an outer layer1211 and an inner layer 1212. Similar to the above, the staple cartridge1200 can comprise a plurality of staples 1220 positioned within thecartridge body 1210. In various embodiments, each staple 1220 cancomprise a base 1222 and one or more staple legs 1221 extendingtherefrom. In at least one such embodiment, the staple legs 1221 can beinserted into the inner layer 1212 and seated to a depth in which thebases 1222 of the staples 1220 abut and/or are positioned adjacent tothe bottom surface 1218 of the inner layer 1212, for example. In theembodiment depicted in FIGS. 23 and 24, the inner layer 1212 does notcomprise staple cavities configured to receive a portion of the staples1220 while, in other embodiments, the inner layer 1212 can comprise suchstaple cavities. In various embodiments, further to the above, the innerlayer 1212 can be comprised of a compressible material, such asbioabsorbable foam and/or oxidized regenerated cellulose (ORC), forexample, which can be configured to allow the cartridge body 1210 tocollapse when a compressive load is applied thereto. In variousembodiments, the inner layer 1212 can be comprised of a lyophilized foamcomprising polylactic acid (PLA) and/or polyglycolic acid (PGA), forexample. The ORC may be commercially available under the trade nameSurgicel and can comprise a loose woven fabric (like a surgical sponge),loose fibers (like a cotton ball), and/or a foam. In at least oneembodiment, the inner layer 1212 can be comprised of a materialincluding medicaments, such as freeze-dried thrombin and/or fibrin, forexample, contained therein and/or coated thereon which can bewater-activated and/or activated by fluids within the patient's body,for example. In at least one such embodiment, the freeze-dried thrombinand/or fibrin can be held on a Vicryl (PGA) matrix, for example. Incertain circumstances, however, the activatable medicaments can beunintentionally activated when the staple cartridge 1200 is insertedinto a surgical site within the patient, for example. In variousembodiments, referring again to FIGS. 23 and 24, the outer layer 1211can be comprised of a water impermeable, or at least substantially waterimpermeable, material such that liquids do not come into contact with,or at least substantially contact, the inner layer 1212 until after thecartridge body 1210 has been compressed and the staple legs havepenetrated the outer layer 1211 and/or after the outer layer 1211 hasbeen incised in some fashion. In various embodiments, the outer layer1211 can be comprised of a buttress material and/or plastic material,such as polydioxanone (PDS) and/or polyglycolic acid (PGA), for example.In certain embodiments, the outer layer 1211 can comprise a wrap whichsurrounds the inner layer 1212 and the staples 1220. More particularly,in at least one embodiment, the staples 1220 can be inserted into theinner layer 1212 and the outer layer 1211 can be wrapped around thesub-assembly comprising the inner layer 1212 and the staples 1220 andthen sealed.

In various embodiments, referring now to FIGS. 25 and 26, a staplecartridge, such as staple cartridge 1300, for example, can comprise acompressible, implantable cartridge body 1310 including an outer layer1311 and an inner layer 1312. Similar to the above, the staple cartridge1300 can further comprise staples 1320 positioned within the cartridgebody 1310 wherein each staple 1320 can comprise a base 1322 and one ormore legs 1321 extending therefrom. Similar to staple cartridge 1200,the bases 1322 of staples 1320 can extend below the bottom surface 1318of the inner layer 1312 and the outer layer 1311 can surround the bases1322. In at least one such embodiment, the outer layer 1311 can besufficiently flexible so as to envelop each staple base 1322 such thatthe outer layer 1311 conforms to the contour of the bases 1322. In atleast one alternative embodiment, referring again to FIG. 24, the outerlayer 1211 can be sufficiently rigid such that it extends around thebases 1222 without conforming to each base 1222. In any event, invarious embodiments, the outer layer 1311 can be positioned intermediatethe bases 1322 of staples 1320 and a staple cartridge support surface,such as support surfaces 1031 or 1131, for example, supporting thestaple cartridge 1300. In at least one such embodiment, the outer layer1311 can be positioned intermediate the bases 1322 and support slots,such as slots 1032 or 1132, for example, defined in the staple cartridgesupport surface. In at least one such embodiment, further to the above,the outer layer 1311 can be configured to limit the movement of thebases 1322 and/or increase the coefficient of friction between the bases1322 and the staple cartridge support surface and/or support slots inorder to reduce relative movement therebetween. In various alternativeembodiments, referring now to FIGS. 27 and 28, the outer layer of astaple cartridge, such as staple cartridge 1400, for example, may notentirely surround the staples positioned therein. In at least one suchembodiment, an outer layer 1411 of a compressible, implantable cartridgebody 1410 may be assembled to the inner layer 1412 before the staplelegs 1421 of staples 1420 are inserted into the cartridge body 1410. Asa result of the above, the bases 1422 of staples 1420 may extend outsideof the outer layer 1411 and, in at least one such embodiment, the bases1422 may be positioned directly into the support slots 1032 or 1132within the staple cartridge support surfaces 1031 or 1131, for example.In various embodiments, the staple legs 1421 may incise the outer layer1411 when they are inserted therethrough. In various circumstances, theholes created by the staple legs 1421 may closely surround the staplelegs 1421 such that very little, if any, fluid can leak between thestaple legs 1421 and the outer layer 1411 which can reduce thepossibility of, or prevent, the medicament contained within the staplecartridge body 1410 from being activated and/or leaking out of thecartridge body 1410 prematurely.

As discussed above, referring again to FIGS. 23 and 24, the legs 1221 ofthe staples 1220 can be embedded within the cartridge body 1210 and thebases 1222 of staples 1220 may extend outwardly from the bottom surface1218 of the inner layer 1212. In various embodiments, further to theabove, the inner layer 1212 may not comprise staple cavities configuredto receive the staples 1220. In various other embodiments, referring nowto FIGS. 29 and 30, a staple cartridge, such as staple cartridge 1500,for example, may comprise a compressible, implantable cartridge body1510 comprising staple cavities 1515 which can be configured to receiveat least a portion of the staples 1520 therein. In at least one suchembodiment, a top portion of the staple legs 1521 of the staples 1520may be embedded in the inner layer 1512 while a bottom portion of thestaple legs 1521, and the bases 1522, may be positioned within thestaple cavities 1515. In certain embodiments, the bases 1522 may beentirely positioned in the staple cavities 1515 while, in someembodiments, the bases 1522 may at least partially extend below thebottom surface 1518 of the inner layer 1512. Similar to the above, theouter layer 1511 may enclose the inner layer 1512 and the staples 1520positioned therein. In certain other embodiments, referring now to FIG.31, a staple cartridge 1600 may comprise staples 1620 positioned withinstaple cavities 1615 in a compressible, implantable cartridge body 1610wherein at least a portion of the staples 1620 are not enclosed by theouter layer 1611. In at least one such embodiment, each staple 1620 cancomprise staple legs 1621 which are at least partially embedded in theinner layer 1612 and, in addition, bases 1622 which extend outwardlyaround the outer layer 1611.

In various embodiments, referring now to FIGS. 32 and 33, a staplecartridge, such as staple cartridge 1700, for example, can comprise acompressible, implantable cartridge body 1710 and a plurality of staples1720 at least partially positioned within the cartridge body 1710. Thecartridge body 1710 can comprise an outer layer 1711, an inner layer1712, and, in addition, an alignment matrix 1740 which can be configuredto align and/or retain the staples 1720 in position within the cartridgebody 1710. In at least one embodiment, the inner layer 1712 can comprisea recess 1741 which can be configured to receive the alignment matrix1740 therein. In various embodiments, the alignment matrix 1140 can bepress-fit within the recess 1741 and/or otherwise suitably secured tothe inner layer 1712 utilizing at least one adhesive, such as fibrinand/or protein hydrogel, for example. In at least one embodiment, therecess 1741 can be configured such that the bottom surface 1742 ofalignment matrix 1740 is aligned, or at least substantially aligned,with the bottom surface 1718 of the inner layer 1712. In certainembodiments, the bottom surface 1742 of the alignment matrix can berecessed with respect to and/or extend from the bottom surface 1718 ofthe second layer 1712. In various embodiments, each staple 1720 cancomprise a base 1722 and one or more legs 1721 extending from the base1722, wherein at least a portion of the staple legs 1721 can extendthrough the alignment matrix 1740. The alignment matrix 1740 can furthercomprise a plurality of apertures and/or slots, for example, extendingtherethrough which can be configured to receive the staple legs 1721therein. In at least one such embodiment, each aperture can beconfigured to closely receive a staple leg 1721 such that there islittle, if any, relative movement between the staple leg 1721 and thesidewalls of the aperture. In certain embodiments, the alignment matrixapertures may not extend entirely through the alignment matrix 1740 andthe staple legs 1721 may be required to incise the alignment matrix 1740as the staple legs 1721 are pushed therethrough.

In various embodiments, the alignment matrix 1740 can be comprised of amolded plastic body which, in at least one embodiment, can be stiffer orless compressible than the inner layer 1712 and/or the outer layer 1711.In at least one such embodiment, the alignment matrix 1740 can becomprised of a plastic material and/or any other suitable material, suchas polydioxanone (PDS) and/or polyglycolic acid (PGA), for example. Incertain embodiments, the alignment matrix 1740 can be assembled to theinner layer 1712 and the staple legs 1721 can thereafter be insertedthrough the alignment matrix 1740 and embedded into the inner layer1712. In various embodiments, the bottom surface 1742 of the alignmentmatrix 1740 can comprise one or more grooves, slots, or troughs, forexample, which can be configured to at least partially receive the bases1722 of the staples 1720. Similar to the above, the outer layer 1711 canthen be placed around the subassembly comprising the inner layer 1712,the alignment matrix 1740, and the staples 1720. Alternatively, theouter layer 1711 can be placed around a subassembly comprising the innerlayer 1712 and the alignment matrix 1740 wherein the staples 1720 can bethereafter inserted through the outer layer 1711, the alignment matrix1740, and the inner layer 1712. In any event, as a result of the above,the inner layer 1712, the alignment matrix 1740, and/or the outer layer1711 can be configured to retain the staples 1720 in position untiland/or after they are deformed by an anvil as described above. In atleast one such embodiment, the alignment matrix 1740 can serve to holdthe staples 1720 in place before the staple cartridge 1700 is implantedwithin a patient and, in addition, secure the tissue along the stapleline after the staple cartridge 1700 has been implanted. In at least oneembodiment, the staples 1720 may be secured within the alignment matrix1740 without being embedded in the inner layer 1712 and/or the outerlayer 1711, for example.

In various embodiments, referring now to FIGS. 34-40, a staplecartridge, such as staple cartridge 1800, for example, can be assembledby compressing an inner layer 1812, inserting staples, such as staples1820, for example, into the inner layer 1812, and wrapping the innerlayer 1812 with an outer layer 1811. Referring primarily to FIG. 34, acompressible inner layer 1812 is illustrated as comprising a pluralityof staple cavities 1815 defined therein, although other embodiments areenvisioned in which the inner layer 1812 does not comprise staplecavities, as described above. Referring now to FIG. 35, the compressibleinner layer 1812 can be positioned intermediate a transfer plate 1850and a support plate 1860 and compressed between the compression surfaces1852 and 1862 thereof, respectively. As illustrated in FIG. 35, the topand bottom surfaces of the inner layer 1812 can be compressed toward oneanother and, in response thereto, the inner layer 1812 can bulgeoutwardly in the lateral directions. In certain embodiments, the innerlayer 1812 can be compressed to a height which is approximatelyone-third of its original height, for example, and can have a height orthickness between approximately 0.06″ and approximately 0.08″ in itscompressed state, for example. As also illustrated in FIG. 35, thetransfer plate 1850 can further comprise a plurality of staples, such asstaples 1820, for example, positioned within a plurality of staple wells1853. In addition, the transfer plate 1850 can further comprise aplurality of drivers 1851 which can be configured to push the staples1820 upwardly and out of the staple wells 1853. Referring now to FIG.36, the drivers 1851 can be utilized to push the staple legs 1821 of thestaples 1820 into and through the compressed inner layer 1812. Invarious embodiments, the drivers 1851 can be configured such that thetop surfaces thereof are positioned flush, or at least nearly flush,with the compression surface 1852 of the transfer plate 1850 when thestaples 1820 have been fully deployed from the staple wells 1853 oftransfer plate 1850. In certain embodiments, as also illustrated in FIG.36, the support plate 1860 can comprise a plurality of receivingapertures 1861 which can be configured to receive the staple legs 1821,or at least the tips of the staple legs 1821, after they are pushedthrough the inner layer 1812. The receiving apertures 1861, or the like,may be necessitated in embodiments where the inner layer 1812 has beencompressed to a height which is shorter than the height of the staples1820 and, thus, when the staples 1820 have been fully ejected from thestaple wells 1853, the staple legs 1821 may protrude from the topsurface of the compressed inner layer 1812. In certain otherembodiments, the inner layer 1812 may be compressed to a height which istaller than the height of the staples 1820 and, as a result, thereceiving apertures 1861 in support plate 1860 may be unnecessary.

After the staples 1820 have been inserted into the inner layer 1812,referring now to FIG. 37, the support plate 1860 can be moved away fromthe transfer plate 1850 in order to allow the inner layer 1812 todecompress. In such circumstances, the inner layer 1812 can resilientlyre-expand to its original, or at least near-original, uncompressedheight. As the inner layer 1812 re-expands, the height of the innerlayer 1812 can increase such that it exceeds the height of the staples1820 and such that the staple legs 1821 of the staples 1820 no longerprotrude from the top surface of the inner layer 1812. In variouscircumstances, the receiving apertures 1861 can be configured to holdthe staple legs 1821 in position at least until the support plate 1860has been sufficiently moved away such that the legs 1821 are no longerpositioned within the receiving apertures 1861. In such circumstances,the receiving apertures 1861 can assist in maintaining the relativealignment of the staples 1820 within the inner layer 1812 as itre-expands. In various circumstances, the inner layer 1812 and thestaples 1820 positioned therein can comprise a subassembly 1801 which,referring now to FIG. 38, can be inserted into an outer layer 1811, forexample. In at least one such embodiment, the outer layer 1811 cancomprise a cavity 1802 defined therein which can be configured toreceive the subassembly 1801 therein. In various circumstances, a tool,such as pliers 1855, for example, can be utilized to pull the outerlayer 1811 onto the subassembly 1801. Once the subassembly 1801 has beensufficiently positioned within the outer layer 1811, referring now toFIG. 39, the outer layer 1811 can be sealed. In various embodiments, theouter layer 1811 can be sealed utilizing the application of heat energyto a portion thereof. More particularly, in at least one embodiment, theouter layer 1811 can be comprised of a plastic material wherein the openend of the outer layer 1811 can be heat-staked by one or more heatedelements, or irons, 1856 in order to bond and/or seal the perimeter ofthe open end of the outer layer 1811 together. In at least one suchembodiment, referring now to FIG. 40, an excess portion 1857 of theouter layer 1811 can be removed and the staple cartridge 1800 can thenbe used as described herein.

As described above, a staple cartridge can be positioned within and/orsecured to a staple cartridge attachment portion. In variousembodiments, referring now to FIGS. 41 and 42, a staple cartridgeattachment portion can comprise a staple cartridge channel, such asstaple cartridge channel 1930, for example, which can be configured toreceive at least a portion of a staple cartridge, such as staplecartridge 1900, for example, therein. In at least one embodiment, thestaple cartridge channel 1930 can comprise a bottom support surface1931, a first lateral support wall 1940, and a second lateral supportwall 1941. In use, the staple cartridge 1900 can be positioned withinthe staple cartridge channel 1930 such that the staple cartridge 1900 ispositioned against and/or adjacent to the bottom support surface 1931and positioned intermediate the first lateral support wall 1940 and thesecond lateral support wall 1941. In certain embodiments, the firstlateral support wall 1940 and the second lateral support wall 1941 candefine a lateral gap therebetween. In at least one such embodiment, thestaple cartridge 1900 can comprise a lateral width 1903 which is thesame as and/or wider than the lateral gap defined between the supportwalls 1940 and 1941 such that a compressible, implantable cartridge body1910 of the staple cartridge 1900 can fit securely between the walls1940 and 1941. In certain other embodiments, the lateral width 1903 ofthe staple cartridge 1900 can be shorter than the gap defined betweenthe first and second side walls 1940 and 1941. In various embodiments,at least a portion of the walls 1940 and 1941 and the bottom supportsurface 1931 can be defined by a stamped metal channel while, in atleast one embodiment, at least a portion of the lateral support wall1940 and/or lateral support wall 1941 can be comprised of a flexiblematerial, such as an elastomeric material, for example. Referringprimarily to FIG. 41, the first side wall 1940 and the second side wall1941 of the staple cartridge channel 1930 can each be comprised of arigid portion 1933 extending upwardly from the bottom support surface1931 and a flexible portion 1934 extending upwardly from the rigidportions 1933.

In various embodiments, further to the above, the cartridge body 1910 ofstaple cartridge 1900 can be comprised of one or more compressiblelayers, such as first layer 1911 and second layer 1912, for example.When the cartridge body 1910 is compressed against the bottom supportsurface 1931 by an anvil, as described above, the side portions of thecartridge body 1910 can expand laterally. In embodiments where thestaple cartridge 1930 is comprised of rigid side walls, the lateralexpansion of the cartridge body 1910 can be prevented, or at leastlimited, by the rigid side walls and, as a result, a significant amountof internal pressure, or stress, can be developed within the cartridgebody 1910. In embodiments where at least a portion of the staplecartridge 1930 is comprised of flexible side walls, the flexible sidewalls can be configured to flex laterally and permit the side portionsof the cartridge body 1910 to expand laterally, thereby reducing theinternal pressure, or stress, generated within the cartridge body 1910.In embodiments where the cartridge channel does not comprise lateralside walls, or comprises lateral sidewalls which are relatively shorterthan the staple cartridge, the side portions of the staple cartridge mayexpand laterally uninhibited, or at least substantially uninhibited. Inany event, referring now to FIG. 42, a staple cartridge channel 2030 cancomprise lateral sidewalls 2040 and 2041 which can be entirely comprisedof a flexible material, such as an elastomeric material, for example.The staple cartridge channel 2030 can further comprise lateral slots2033 extending along the sides of the bottom support surface 2031 of thestaple cartridge channel 2030 which can be configured to receive andsecure at least a portion of the lateral sidewalls 2040 and 2041therein. In certain embodiments, the lateral side walls 2040 and 2041can be secured in the slots 2033 via a snap-fit and/or press-fitarrangement while, in at least some embodiments, the lateral side walls2040 and 2041 can be secured in the slots 2033 by one or more adhesives.In at least one embodiment, the sidewalls 2040 and 2041 may bedetachable from the bottom support surface 2031 during use. In anyevent, a compressible, implantable cartridge body 2010 can be detachedand/or disengaged from the lateral side walls 2040 and 2041 when thecartridge body 2010 is implanted with the staples 2020.

In various embodiments, referring now to FIG. 43, a surgical instrumentcan comprise a shaft 2150 and an end effector extending from the distalend of the shaft 2150. The end effector can comprise, similar to theabove, a staple cartridge channel 2130, an anvil 2140 movable between anopen position and a closed position, and a staple cartridge 2100positioned intermediate the staple cartridge channel 2130 and the anvil2140. Also similar to the above, the staple cartridge 2100 can comprisea compressible, implantable cartridge body 2110 and a plurality ofstaples 2120 positioned in the cartridge body 2110. In variousembodiments, the staple cartridge channel 2130 can comprise, one, abottom support surface 2131 against which the staple cartridge 2100 canbe positioned, two, a distal end 2135 and, three, a proximal end 2136.In at least one embodiment, as illustrated in FIG. 43, the staplecartridge 2100 can comprise a first end 2105 which can be positionablein the distal end 2135 of the staple cartridge channel 2130 and a secondend 2106 which can be positionable in the proximal end 2136 of thestaple cartridge channel 2130. In various embodiments, the distal end2135 of the staple cartridge channel 2130 can comprise at least onedistal retention feature, such as a retention wall 2137, for example,and, similarly, the proximal end 2136 can comprise at least one proximalretention feature, such as a retention wall 2138, for example. In atleast one such embodiment, the distal retention wall 2137 and theproximal retention wall 2138 can define a gap therebetween which can beequal to or less than the length of the staple cartridge 2100 such thatthe staple cartridge 2100 can fit securely within the staple cartridgechannel 2130 when the staple cartridge 2100 is inserted therein.

In various embodiments, referring again to FIGS. 23 and 24, a staplecartridge, such as staple cartridge 1200, for example, can comprise aflat, or at least substantially flat, tissue-contacting surface 1219. Inat least one such embodiment, the staple cartridge body 1210 of staplecartridge 1200 can comprise a first end 1205 which can be defined by afirst height, or thickness, 1207 and a second end 1206 which can bedefined by a second height, or thickness, 1208, wherein the first height1207 can be equal to, or at least substantially equal to, the secondheight 1208. In certain embodiments, the cartridge body 1210 cancomprise a constant, or at least substantially constant, height, orthickness, between the first end 1205 and the second end 1206. In atleast one such embodiment, the tissue-contacting surface 1219 can beparallel, or at least substantially parallel, to the bottom surface 1218of the cartridge body 1210. In various embodiments, referring once againto FIG. 43, the first end 2105 of the cartridge body 2110 of staplecartridge 2100 can be defined by a first height 2107 which is differentthan a second height 2108 of the second end 2106. In the illustratedembodiment, the first height 2107 is larger than the second height 2108,although the second height 2108 could be larger than the first height2107 in alternative embodiments. In various embodiments, the height ofthe cartridge body 2110 can decrease linearly and/or geometricallybetween the first end 2105 and the second end 2106. In at least one suchembodiment, the tissue-contacting surface 2119, which extends betweenthe first end 2105 and the second end 2106, can be oriented along anangle defined therebetween. In at least one such embodiment, thetissue-contacting surface 2119 may not be parallel to the bottom surface2118 of the cartridge body 2110 and/or parallel to the support surface2131 of the staple cartridge channel 2130.

In various embodiments, referring again to FIGS. 43 and 44, the anvil2140 can comprise a tissue-contacting surface 2141 which can beparallel, or at least substantially parallel, to the support surface2131 of the staple cartridge channel 2130 when the anvil 2140 is in aclosed position, as illustrated in FIG. 44. When the anvil 2140 is in aclosed position, the anvil 2140 can be configured to compress the firstend 2105 of the staple cartridge 2100 more than the second end 2106owing to the taller height of the first end 2105 and the shorter heightof the second end 2106. In some circumstances, including circumstanceswhere the tissue T positioned intermediate the tissue contactingsurfaces 2119 and 2141 has a constant, or at least substantiallyconstant, thickness, the pressure generated within the tissue T and thecartridge 2100 can be greater at the distal end of the end effector thanthe proximal end of the end effector. More particularly, when the tissueT between the anvil 2140 and the staple cartridge 2100 has asubstantially constant thickness, the tissue T positioned intermediatethe distal end 2145 of the anvil 2140 and the first end 2105 of thestaple cartridge 2100 can be more compressed than the tissue Tpositioned intermediate the proximal end 2146 of the anvil 2140 and thesecond end 2106 of the staple cartridge 2100. In various embodiments, apressure gradient can be generated within the tissue T between theproximal end and the distal end of the end effector. More particularly,in at least one embodiment, when the tissue T between the anvil 2140 andthe staple cartridge 2100 has a substantially constant thickness and theheight of the staple cartridge 2100 decreases linearly from the distalend to the proximal end of the end effector, the pressure within thetissue T can decrease linearly from the distal end of the end effectorto the proximal end of the end effector. Similarly, in at least oneembodiment, when the tissue T between the anvil 2140 and the staplecartridge 2100 has a substantially constant thickness and the height ofthe staple cartridge 2100 decreases geometrically from the distal end tothe proximal end of the end effector, the pressure within the tissue Tcan decrease geometrically from the distal end of the end effector tothe proximal end of the end effector.

In various embodiments, referring again to FIG. 43, the tissue Tpositioned intermediate the staple cartridge 2100 and the anvil 2140 maynot have a constant thickness throughout. In at least one suchcircumstance, the tissue T positioned between the proximal end 2146 ofthe anvil 2140 and the second end 2106 of the staple cartridge 2100 maybe thicker than the tissue T positioned between the distal end 2145 ofthe anvil 2140 and the first end 2105 of the staple cartridge 2100. Insuch circumstances, as a result, the thicker tissue T may be generallypositioned above the shorter proximal end 2106 of the staple cartridge2100 and the thinner tissue T may be generally positioned above thetaller distal end 2105. In use, the firing collar 2152 of the shaft 2150can be advanced distally along the shaft spine 2151 such that the firingcollar 2152 engages the cam portion 2143 of the anvil 2140 and rotatesthe anvil 2140 toward the staple cartridge 2100 as illustrated in FIG.44. Once the anvil 2140 has been rotated into a fully-closed position,the tissue T may be compressed between the tissue-contacting surfaces2119 and 2141 and, even though the height of the staple cartridge 2100may not be constant between the proximal and distal ends of the endeffector, the pressure or compressive forces applied to the tissue T maybe constant, or at least substantially constant, thereacross. Moreparticularly, as the thinner tissue T may be associated with the tallerheight of the staple cartridge 2100 and the thicker tissue T may beassociated with the shorter height of the staple cartridge 2100, thecumulative, or summed, height of the tissue T and the staple cartridge2100 may be constant, or at least substantially constant, between theproximal and distal ends of the end effector and, as a result, thecompression of this cumulative height by the anvil 2140 may be constant,or at least substantially constant, thereacross.

In various embodiments, referring again to FIGS. 43 and 44, the staplecartridge 2100 can comprise an asymmetrical configuration. In at leastone such embodiment, for example, the height of the staple cartridge2100 at the first end 2105 thereof may be higher than the height of thestaple cartridge 2100 at the second end 2106 thereof. In certainembodiments, the staple cartridge 2100 and/or the staple cartridgechannel 2130 can comprise one or more alignment and/or retentionfeatures which can be configured to assure that the staple cartridge2100 can only be positioned within the staple cartridge channel 2130 inone orientation, i.e., an orientation in which the first end 2105 ispositioned in the distal end 2135 of the staple cartridge channel 2130and the second end 2106 is positioned in the proximal end 2136. Invarious alternative embodiments, the staple cartridge 2100 and/or thestaple cartridge channel 2130 can comprise one or more alignment and/orretention features which can be configured to permit the staplecartridge 2100 to be positioned within the staple cartridge channel 2130in more than one orientation. Referring now to FIG. 45, for example, thestaple cartridge 2100 can be positioned within the staple cartridgechannel 2130 such that the first end 2105 of the staple cartridge 2100can be positioned in the proximal end 2136 of the staple cartridgechannel 2130 and the second end 2106 can be positioned in the distal end2135. In various embodiments, as a result, the shorter height of thestaple cartridge 2100 can be positioned proximate the distal retentionwall 2137 and the taller height of the staple cartridge 2100 can bepositioned proximate to the proximal retention wall 2138. In at leastone such embodiment, the staple cartridge 2100 can be suitably arrangedto apply a constant, or at least substantially constant, clampingpressure to tissue T having a thicker portion within the distal end ofthe end effector and a thinner portion within the proximal end of theend effector. In various embodiments, the staple cartridge 2100, forexample, can be selectively oriented within the staple cartridge channel2130. In at least one such embodiment, the alignment and/or retentionfeatures of the staple cartridge 2100 can be symmetrical and a surgeoncan selectively orient the staple cartridge 2100 within the staplecartridge channel 2130 in the orientations depicted in FIG. 43 and FIG.45, for example.

Further to the above, the implantable cartridge body 2110 can comprise alongitudinal axis 2109 which, when the staple cartridge 2100 ispositioned in the staple cartridge channel 2130, can extend between theproximal and distal ends of the end effector. In various embodiments,the thickness of the cartridge body 2110 can generally decrease and/orgenerally increase between the first end 2105 and the second end 2106along the longitudinal axis 2109. In at least one such embodiment, thedistance, or height, between the bottom surface 2118 and thetissue-contacting surface 2119 can generally decrease and/or generallyincrease between the first end 2105 and the second end 2106. In certainembodiments, the thickness of the cartridge body 2110 can both increaseand decrease along the longitudinal axis 2109. In at least one suchembodiment, the thickness of the cartridge body 2110 can comprise one ormore portions which increase in thickness and one or more portions whichcan decrease in thickness. In various embodiments, the staple cartridge2100 can comprise a plurality of staples 2120 positioned therein. Inuse, as described above, the staples 2120 can be deformed when the anvil2140 is moved into a closed position. In certain embodiments, eachstaple 2120 can have the same, or at least substantially the same,height. In at least one such embodiment, the height of a staple can bemeasured from the bottom of the base of the staple to the top, or tip,of the tallest leg of the staple, for example.

In various embodiments, the staples within a staple cartridge can havedifferent staple heights. In at least one such embodiment, a staplecartridge can comprise a first group of staples having a first stapleheight which are positioned in a first portion of a compressiblecartridge body and a second group of staples having a second stapleheight which are positioned in a second portion of the compressiblecartridge body. In at least one embodiment, the first staple height canbe taller than the second staple height and the first group of staplescan be positioned in the first end 2105 of the staple cartridge 2100while the second group of staples can be positioned in the second end2106. Alternatively, the taller first group of staples can be positionedin the second end 2106 of the staple cartridge 2100 while the shortersecond group of staples can be positioned in the first end 2105. Incertain embodiments, a plurality of staple groups, each group having adifferent staple height, can be utilized. In at least one suchembodiment, a third group having an intermediate staple height can bepositioned in the cartridge body 2110 intermediate the first group ofstaples and the second group of staples. In various embodiments, eachstaple within a staple row in the staple cartridge can comprise adifferent staple height. In at least one embodiment, the tallest staplewithin a staple row can be positioned on a first end of a staple row andthe shortest staple can be positioned on an opposite end of the staplerow. In at least one such embodiment, the staples positionedintermediate the tallest staple and the shortest staple can be arrangedsuch that the staple heights descend between the tallest staple and theshortest staple, for example.

In various embodiments, referring now to FIG. 46, an end effector of asurgical stapler can comprise an anvil 2240, a staple cartridge channel2230, and a staple cartridge 2200 supported by the staple cartridgechannel 2230. The staple cartridge 2200 can comprise a compressible,implantable cartridge body 2210 and a plurality of staples, such asstaples 2220 a and staples 2220 b, for example, positioned therein. Invarious embodiments, the staple cartridge channel 2230 can comprise acartridge support surface 2231 and a plurality of staple support slots,such as support slots 2232 a and 2232 b, for example, defined therein.In at least one such embodiment, the staple cartridge 2200 can comprisetwo outer rows of staples 2220 a and two inner rows of staples 2220 b,wherein the support slots 2232 a can be configured to support thestaples 2220 a and the support slots 2232 b can be configured to supportthe staples 2220 b. Referring to FIGS. 46 and 47, the anvil 2240 cancomprise a plurality of staple forming pockets 2242 defined thereinwhich can be configured to receive and deform the staples 2220 a and2220 b when the anvil 2240 is moved toward the staple cartridge 2200. Inat least one such embodiment, the bottom surfaces of the support slots2232 a can be a first distance 2201 a away from the top surfaces of thestaple forming pockets 2242 while the bottom surfaces of the supportslots 2232 b can be a second distance 2201 b away from the top surfacesof the staple forming pockets 2242. In at least one such embodiment, thesupport slots 2232 b are positioned closer to the anvil 2240 owing tothe raised step in the support surface 2231 in which they are defined.Owing to the different distances 2201 a and 2201 b, in variousembodiments, the outer rows of staples 2220 a and the inner rows ofstaples 2220 b can be deformed to different formed heights. In variouscircumstances, staples deformed to different formed heights can applydifferent clamping pressures or forces to the tissue T being stapled. Inaddition to the above, the staples can begin with different unformedstaple heights. In at least one such embodiment, referring again to FIG.46, the outer staples 2220 a can have an initial, unformed height whichis greater than the initial, unformed height of the inner staples 2220b. As illustrated in FIGS. 46 and 47, the inner staples 2220 b, whichhave a shorter unformed height than the outer staples 2220 a, can alsohave a shorter formed height than the outer staples 2220 b. In variousalternative embodiments, the inner staples 2220 b may have a tallerunformed height than the outer staples 2220 a yet have a shorterdeformed staple height than the outer staples 2220 a.

In various embodiments, further to the above, the anvil 2240 can bemoved into a closed position, as illustrated in FIG. 47, in order tocompress the cartridge body 2210 and deform the staples 2220 a and 2220b. In certain embodiments, a surgical stapler comprising the endeffector depicted in FIGS. 46 and 47, for example, can further comprisea cutting member which can be configured to transect the tissue Tpositioned intermediate the anvil 2240 and the staple cartridge 2200. Inat least one such embodiment, the anvil 2240, the staple cartridgechannel 2230 and/or the staple cartridge 2200 can define a slotconfigured to slidably receive a cutting member therein. Moreparticularly, the anvil 2240 can comprise a slot portion 2249, thestaple cartridge channel 2230 can comprise a slot portion 2239, and thestaple cartridge 2200 can comprise a slot portion 2203 which can bealigned, or at least substantially aligned, with one another when theanvil 2240 is in a closed, or at least substantially closed, position.In various embodiments, the cutting member can be moved from theproximal end of the end effector toward the distal end of the endeffector after the anvil 2240 has been closed and the staples 2220 a,2220 b have been deformed. In at least one embodiment, the cuttingmember can be moved independently of the staple deformation process. Incertain embodiments, the cutting member can be advanced at the same timethat the staples are being deformed. In any event, in at least oneembodiment, the cutting member can be configured to incise the tissuealong a path positioned intermediate the inner rows of staples 2220 b.

In various embodiments, as illustrated in FIG. 47, the inner staples2220 b can be formed to a shorter height than the outer staples 2220 awherein the inner staples 2220 b can apply a larger clamping pressure orforce to the tissue adjacent to the cut line created by the cuttingmember. In at least one such embodiment, the larger clamping pressure orforce created by the inner staples 2220 b can provide varioustherapeutic benefits such as reducing bleeding from the incised tissue Twhile the smaller clamping pressure created by the outer staples 2220 acan provide flexibility within the stapled tissue. In variousembodiments, referring again to FIGS. 46 and 47, the anvil 2240 canfurther comprise at least one piece of buttress material, such asbuttress material 2260, for example, attached thereto. In at least onesuch embodiment, the legs of the staples 2220 a, 2220 b can beconfigured to incise the buttress material 2260 and/or pass throughapertures in the buttress material 2260 when the staple cartridge 2200is compressed by the anvil 2240 and thereafter contact the stapleforming pockets 2242 in the anvil 2240. As the legs of the staples 2220a, 2220 b are being deformed, the legs can contact and/or incise thebuttress material 2260 once again. In various embodiments, the buttressmaterial 2260 can improve the hemostasis of and/or provide strength tothe tissue being stapled.

In various embodiments, referring again to FIGS. 46 and 47, the bottomsurface of the cartridge body 2210 can comprise a stepped contour whichmatches, or at least substantially matches, the stepped contour of thecartridge support surface 2231. In certain embodiments, the bottomsurface of the cartridge body 2210 can deform to match, or at leastsubstantially match, the contour of the cartridge support surface 2231.In various embodiments, referring now to FIG. 48, an end effector,similar to the end effector depicted in FIG. 46, for example, cancomprise a staple cartridge 2300 positioned therein. The staplecartridge 2300 can comprise a compressible, implantable body 2310comprising an inner layer 2312 and an outer layer 2311 wherein, furtherto the above, the outer layer 2311 can be comprised of a waterimpermeable material in at least one embodiment. In various embodiments,the outer layer 2311 can extend around the staples 2220 a, 2220 b andcan be positioned intermediate the staples 2220 a, 2220 b and thesupport slots 2232 a, 2232 b, respectively. In various embodiments,referring now to FIG. 49, an end effector, similar to the end effectordepicted in FIG. 46, for example, can comprise a staple cartridge 2400positioned therein. Similar to the staple cartridge 2300, thecompressible, implantable cartridge body 2410 of staple cartridge 2400can comprise an inner layer 2412 and an outer layer 2411; however; in atleast one embodiment, the cartridge body 2410 may not comprise a cuttingmember slot therein. In at least one such embodiment, the cutting membermay be required to incise the inner layer 2412 and/or the outer layer2411, for example, as it is advanced through the staple cartridge.

In various embodiments, referring now to FIG. 50, an end effector of asurgical stapler can comprise an anvil 2540, a staple cartridge channel2530, and a staple cartridge 2500 positioned in the staple cartridgechannel 2530. Similar to the above, the staple cartridge 2500 cancomprise a compressible, implantable cartridge body 2510, outer rows ofstaples 2220 a, and inner rows of staples 2220 b. The staple cartridgechannel 2530 can comprise a flat, or an at least substantially flat,cartridge support surface 2531 and staple support slots 2532 definedtherein. The anvil 2540 can comprise a stepped surface 2541 and aplurality of staple forming pockets, such as forming pockets 2542 a and2542 b, for example, defined therein. Similar to the above, the formingpockets 2542 a and the support slots 2532 can define a distancetherebetween which is greater than the distance between the formingpockets 2452 b and the support slots 2532. In various embodiments, theanvil 2540 can further comprise a piece of buttress material 2560attached to the stepped surface 2541 of the anvil 2540. In at least onesuch embodiment, the buttress material 2560 can conform, or at leastsubstantially conform, to the stepped surface 2541. In variousembodiments, the buttress material 2560 can be removably attached to thesurface 2541 by at least one adhesive, such as fibrin and/or proteinhydrogel, for example. In certain embodiments, the cartridge body 2510can also comprise a stepped profile which, in at least one embodiment,parallels, or at least substantially parallels, the stepped surface 2541of the anvil 2540. More particularly, in at least one embodiment, theanvil 2540 can comprise steps 2548 extending toward the staple cartridge2500 wherein the steps 2548 can comprise a step height which equals, orat least substantially equals, the step height of the steps 2508extending from the cartridge body 2510. In at least one such embodiment,as a result of the above, the amount of the compressible cartridge body2510 that can be captured in the first staples 2220 a can be differentthan the amount of the compressible cartridge body 2510 that can becaptured in the second staples 2220 b, for example.

In various embodiments, referring now to FIG. 51, an end effector cancomprise an anvil 2640, a staple cartridge channel 2530, and a staplecartridge 2600 positioned therebetween. The staple cartridge 2600 cancomprise a compressible, implantable cartridge body 2610 including aninner layer 2612, an outer layer 2611, and a plurality of staples, suchas staples 2220 a and 2200 b, for example, positioned therein. Invarious embodiments, the anvil 2640 can comprise a plurality of stapleforming pockets 2642 in surface 2641 and the staple cartridge channel2530 can comprise a plurality of staple forming slots 2532 defined inthe support surface 2531. As illustrated in FIG. 51, the anvil surface2641 can be parallel, or at least substantially parallel, to thecartridge support surface 2531 wherein each forming pocket 2642 can bepositioned an equal, or at least substantially equal, distance away froman opposing and corresponding staple support slot 2532. In variousembodiments, the staple cartridge 2600 can comprise staples having thesame, or at least substantially the same, initial, unformed stapleheight and, in addition, the same, or at least substantially the same,formed staple height. In certain other embodiments, the outer rows ofstaples can comprise staples 2220 a and the inner rows of staples cancomprise staples 2220 b wherein, as discussed above, the staples 2220 aand 2220 b can have different unformed staple heights. When the anvil2640 is moved toward the staple cartridge 2600 into a closed position,the staples 2220 a and 2220 b can be formed such that they have thesame, or at least substantially the same, formed staple height. In atleast one such embodiment, as a result of the above, the formed outerstaples 2220 a and the inner staples 2220 b may have the same, or atleast substantially the same, amount of compressible cartridge body 2610contained therein; however, as the outer staples 2220 a have a tallerunformed staple height than the inner staples 2220 b and may have thesame formed staple height nonetheless, a greater clamping pressure canbe generated in the outer staples 2220 a than the inner staples 2220 b,for example.

In various embodiments, referring now to FIG. 52, an end effector of asurgical stapler can comprise an anvil 2740, a staple cartridge channel2530, and a staple cartridge 2700 positioned within the staple cartridgechannel 2530. Similar to the above, the staple cartridge 2700 cancomprise a compressible, implantable cartridge body 2710 comprising aninner layer 2712, an outer layer 2711, and a plurality of staples, suchas staples 2220 a and 2220 b, for example, positioned therein. In atleast one embodiment, the thickness of the cartridge body 2710 can varyacross its width. In at least one such embodiment, the cartridge body2710 can comprise a center portion 2708 and side portions 2709, whereinthe center portion 2708 can comprise a thickness which is greater thanthe thickness of the side portions 2709. In various embodiments, thethickest portion of the cartridge body 2710 can be located at the centerportion 2708 while the thinnest portion of the cartridge body 2710 canbe located at the side portions 2709. In at least one such embodiment,the thickness of the cartridge body 2710 can decrease gradually betweenthe center portion 2708 and the side portions 2709. In certainembodiments, the thickness of the cartridge body 2710 can decreaselinearly and/or geometrically between the center portion 2708 and theside portions 2709. In at least one such embodiment, thetissue-contacting surface 2719 of cartridge body 2710 can comprise twoinclined, or angled, surfaces which slope downwardly from the centerportion 2708 toward the side portions 2709. In various embodiments, theanvil 2740 can comprise two inclined, or angled, surfaces whichparallel, or at least substantially parallel, the inclinedtissue-contacting surfaces 2719. In at least one embodiment, the anvil2740 can further comprise at least one piece of buttress material 2760attached to the inclined surfaces of the anvil 2740.

In various embodiments, further to the above, the inner rows of staplesin the staple cartridge 2700 can comprise the taller staples 2220 a andthe outer rows of staples can comprise the shorter staples 2220 b. In atleast one embodiment, the taller staples 2220 a can be positioned withinand/or adjacent to the thicker center portion 2708 while the staples2220 b can be positioned within and/or adjacent to the side portions2709. In at least one such embodiment, as a result of the above, thetaller staples 2220 a can capture more material of the implantablecartridge body 2710 than the shorter staples 2220 b. Such circumstancescould result in the staples 2220 a applying a greater clamping pressureto the tissue T than the staples 2220 b. In certain embodiments, eventhough the taller staples 2220 a may capture more material of thecartridge body 2710 therein than the shorter staples 2220 b, the tallerstaples 2220 a may have a taller formed staple height than the shorterstaples 2220 b owing to the inclined arrangement of the staple formingpockets 2742 a and 2742 b. Such considerations can be utilized toachieve a desired clamping pressure within the tissue captured by thestaples 2220 a and 2220 b wherein, as a result, the clamping pressure inthe staples 2220 a can be greater than, less than, or equal to theclamping pressure applied to the tissue by the staples 2220 b, forexample. In various alternative embodiments to the end effectorillustrated in FIG. 52, the shorter staples 2220 b can be positionedwithin and/or adjacent to the thicker center portion 2708 of thecartridge body 2710 and the taller staples 2220 a can be positionedwithin and/or adjacent to the thinner side portions 2709. Furthermore,although the staple cartridge 2700 is depicted as comprising inner andouter rows of staples, the staple cartridge 2700 may comprise additionalrows of staples, such as staple rows positioned intermediate the innerand outer rows of staples, for example. In at least one such embodiment,the intermediate staple rows can comprise staples having an unformedstaple height which is intermediate the unformed staple heights of thestaples 2220 a and 2220 b and a formed staple height which isintermediate the formed staple heights of the staples 2220 a and 2220 b,for example.

In various embodiments, referring now to FIG. 53, an end effector of asurgical stapler can comprise an anvil 2840, a staple cartridge channel2530, and a staple cartridge 2800 positioned within the staple cartridgechannel 2530. Similar to the above, the staple cartridge 2800 cancomprise a compressible, implantable cartridge body 2810 comprising aninner layer 2812, an outer layer 2811, and a plurality of staples, suchas staples 2220 a and 2220 b, for example, positioned therein. In atleast one embodiment, the thickness of the cartridge body 2810 can varyacross its width. In at least one such embodiment, the cartridge body2810 can comprise a center portion 2808 and side portions 2809, whereinthe center portion 2808 can comprise a thickness which is less than thethickness of the side portions 2809. In various embodiments, thethinnest portion of the cartridge body 2810 can be located at the centerportion 2808 while the thickest portion of the cartridge body 2810 canbe located at the side portions 2809. In at least one such embodiment,the thickness of the cartridge body 2810 can increase gradually betweenthe center portion 2808 and the side portions 2809. In certainembodiments, the thickness of the cartridge body 2810 can increaselinearly and/or geometrically between the center portion 2808 and theside portions 2809. In at least one such embodiment, thetissue-contacting surface 2819 of cartridge body 2810 can comprise twoinclined, or angled, surfaces which slope upwardly from the centerportion 2808 toward the side portions 2809. In various embodiments, theanvil 2840 can comprise two inclined, or angled, surfaces whichparallel, or at least substantially parallel, the inclinedtissue-contacting surfaces 2819. In at least one embodiment, the anvil2840 can further comprise at least one piece of buttress material 2860attached to the inclined surfaces of the anvil 2840. In variousembodiments, further to the above, the outer rows of staples in thestaple cartridge 2800 can comprise the taller staples 2220 a and theinner rows of staples can comprise the shorter staples 2220 b. In atleast one embodiment, the taller staples 2220 a can be positioned withinand/or adjacent to the thicker side portions 2809 while the staples 2220b can be positioned within and/or adjacent to the center portion 2808.In at least one such embodiment, as a result of the above, the tallerstaples 2220 a can capture more material of the implantable cartridgebody 2810 than the shorter staples 2220 b.

As described above with regard to the embodiment of FIG. 46, forexample, the staple cartridge channel 2230 can comprise a steppedsupport surface 2231 which can be configured to support the staples 2220a and 2220 b at different heights with respect the anvil 2240. Invarious embodiments, the staple cartridge channel 2230 can be comprisedof metal and the steps in the support surface 2231 may be formed in thesupport surface 2231 by a grinding operation, for example. In variousembodiments, referring now to FIG. 54, an end effector of a surgicalinstrument can comprise a staple cartridge channel 2930 comprising asupport insert 2935 positioned therein. More particularly, in at leastone embodiment, the staple cartridge channel 2930 can be formed suchthat it has a flat, or at least substantially flat, support surface2931, for example, which can be configured to support the insert 2935which comprises the stepped surfaces for supporting the staples 2220 aand 2220 b of the staple cartridge 2200 at different heights. In atleast one such embodiment, the insert 2935 can comprise a flat, or atleast substantially flat, bottom surface which can be positioned againstthe support surface 2931. The insert 2935 can further comprise supportslots, grooves, or troughs 2932 a and 2932 b which can be configured tosupport the staples 2220 a and 2220 b, respectively, at differentheights. Similar to the above, the insert 2935 can comprise a knife slot2939 defined therein which can be configured to permit a cutting memberto pass therethrough. In various embodiments, the staple cartridgechannel 2930 can be comprised of the same material as or a differentmaterial than the support insert 2935. In at least one embodiment, thestaple cartridge channel 2930 and the support insert 2935 can both becomprised of metal, for example, while, in other embodiments, the staplecartridge channel 2930 can be comprised of metal, for example, and thesupport insert 2935 can be comprised of plastic, for example. In variousembodiments, the support insert 2935 can be fastened and/or welded intothe staple cartridge channel 2930. In certain embodiments, the supportinsert 2935 can be snap-fit and/or press-fit into the staple cartridgechannel 2930. In at least one embodiment the support insert 2935 can besecured in the staple cartridge channel 2930 using an adhesive.

In various embodiments, referring now to FIG. 55, an end effector of asurgical stapler can comprise an anvil 3040, a staple cartridge channel3030, and a compressible, implantable staple cartridge 3000 positionedin the staple cartridge channel 3030. Similar to the above, the anvil3040 can comprise a plurality of staple-forming pockets 3042 definedtherein and a knife slot 3049 which can be configured to slidablyreceive a cutting member therein. Also similar to the above, the staplecartridge channel 3030 can comprise a plurality of staple support slots3032 defined therein and a knife slot 3039 which can also be configuredto slidably receive a cutting member therein. In various embodiments,the staple cartridge 3000 can comprise a first layer 3011, a secondlayer 3012, and a plurality of staples, such as staples 3020 a and 3020b, for example, positioned therein. In at least one embodiment, thestaples 3020 a can comprise an unformed staple height which is tallerthan the unformed staple height of the staples 3020 b. In variousembodiments, the first layer 3011 can be comprised of a firstcompressible material and the second layer 3012 can be comprised of asecond compressible material. In certain embodiments, the firstcompressible material can be compressed at a rate which is higher thanthe second compressible material while, in certain other embodiments,the first compressible material can be compressed at a rate which islower than the second compressible material. In at least one embodiment,the first compressible material can be comprised of a resilient materialwhich can comprise a first spring rate and the second compressiblematerial can be comprised of a resilient material which can comprise asecond spring rate which is different than the first spring rate. Invarious embodiments, the first compressible material can comprise aspring rate which is greater than the spring rate of the secondcompressible material. In certain other embodiments, the firstcompressible material can comprise a spring rate which is less than thespring rate of the second compressible material. In various embodiments,the first compressible layer can comprise a first stiffness and thesecond compressible layer can comprise a second stiffness, wherein thefirst stiffness is different than the second stiffness. In variousembodiments, the first compressible layer can comprise a stiffness whichis greater than the stiffness of the second compressible layer. Incertain other embodiments, the first compressible layer can comprise astiffness which is less than the stiffness of the second compressiblelayer.

In various embodiments, referring again to FIG. 55, the second layer3012 of the staple cartridge 3000 can comprise a constant, or at leastsubstantially constant, thickness across the width thereof. In at leastone embodiment, the first layer 3011 can comprise a thickness whichvaries across the width thereof. In at least one such embodiment, thefirst layer 3011 can comprise one or more steps 3008 which can increasethe thickness of the cartridge body 3010 in certain portions of thecartridge body 3010, such as the center portion, for example. Referringagain to FIG. 55, the shorter staples 3020 b can be positioned in oraligned with the steps 3008, i.e., the thicker portions of the cartridgebody 3010, and the taller staples 3020 a can be positioned in or alignedwith the thinner portions of the cartridge body 3010. In variousembodiments, as a result of the thicker and thinner portions of thecartridge body 3010, the stiffness of the cartridge body 3010 can begreater along the inner rows of staples 3020 b than the outer rows ofstaples 3020 a. In various embodiments, the first layer 3011 can beconnected to the second layer 3012. In at least one such embodiment, thefirst layer 3011 and the second layer 3012 can comprise interlockingfeatures which can retain the layers 3011 and 3012 together. In certainembodiments, the first layer 3011 can comprise a first laminate and thesecond layer 3012 can comprise a second laminate, wherein the firstlaminate can be adhered to the second laminate by one or more adhesives.In various embodiments, the staple cartridge 3000 can comprise a knifeslot 3003 which can be configured to slidably receive a cutting membertherein.

In various embodiments, referring now to FIG. 56, a staple cartridge3100 can comprise a compressible, implantable cartridge body 3110comprising a single layer of compressible material and, in addition, aplurality of staples, such as staples 3020 b, for example, positionedtherein. In at least one embodiment, the thickness of the cartridge body3110 can vary across the width thereof. In at least one such embodiment,the cartridge body 3110 can comprise steps 3108 extending along the sideportions thereof. In various embodiments, referring now to FIG. 57, astaple cartridge 3200 can comprise a compressible, implantable cartridgebody 3210 comprising a single layer of compressible material and, inaddition, a plurality of staples, such as staples 3020 b, for example,positioned therein. In at least one embodiment, the thickness of thecartridge body 3210 can vary across the width thereof. In at least onesuch embodiment, the cartridge body 3210 can comprise steps 3208extending along the center portion thereof. In various embodiments,referring now to FIG. 58, a staple cartridge 3300 can comprise acompressible, implantable cartridge body 3310 wherein, similar to theabove, the thickness of the cartridge body 3310 can vary across thewidth thereof. In at least one embodiment, the thickness of thecartridge body 3310 can increase geometrically between the side portionsand the center portion of the cartridge body 3310. In at least one suchembodiment, the thickness of the cartridge body 3310 can be defined byan arcuate or curved profile and can comprise an arcuate or curvedtissue-contacting surface 3319. In certain embodiments, the thickness ofthe cartridge body 3310, and the contour of the tissue-contactingsurface 3319, can be defined by one radius of curvature or,alternatively, by several radiuses of curvature, for example. In variousembodiments, referring now to FIG. 59, a staple cartridge 3400 cancomprise a compressible, implantable cartridge body 3410 wherein thethickness of the cartridge body 3410 can increase linearly, or at leastsubstantially linearly, between the side portions and the center portionof the cartridge body 3410.

In various embodiments, referring now to FIG. 60, a staple cartridge3500 can comprise a compressible, implantable cartridge body 3510 and aplurality of staples 3520 positioned therein. The implantable cartridgebody 3510 can comprise a first inner layer 3512, a second inner layer3513, and an outer layer 3511. In at least one embodiment, the firstinner layer 3512 can comprise a first thickness and the second innerlayer 3513 can comprise a second thickness wherein the second innerlayer 3513 can be thicker than the first inner layer 3512. In at leastone alternative embodiment, the first inner layer 3512 can be thickerthan the second inner layer 3513. In another alternative embodiment, thefirst inner layer 3512 can have the same, or at least substantially thesame, thickness as the second inner layer 3513. In certain embodiments,each staple 3520 can comprise a base 3522 and one or more deformablelegs 3521 extending from the base 3522. In various embodiments, each leg3521 can comprise a tip 3523 which is embedded in the first inner layer3511 and, in addition, each base 3522 of the staples 3520 can beembedded in the second inner layer 3512. In at least one embodiment, thefirst inner layer 3512 and/or the second inner layer 3513 can compriseat least one medicament stored therein and, in various embodiments, theouter layer 3511 can encapsulate and seal the first inner layer 3512 andthe second inner layer 3513 such that the medicament does not flow outof the staple cartridge body 3510 until after the outer layer 3511 hasbeen punctured by the staples 3520. More particularly, further to theabove, an anvil can be pushed downwardly against tissue positionedagainst the tissue-contacting surface 3519 of staple cartridge 3500 suchthat the cartridge body 3510 is compressed and the surface 3519 is moveddownwardly toward, and at least partially below, the staple tips 3523such that the tips 3523 rupture or puncture the outer layer 3511. Afterthe outer layer 3511 has been breached by the staple legs 3521, the atleast one medicament M can flow out of the cartridge body 3510 aroundthe staple legs 3521. In various circumstances, additional compressionof the cartridge body 3510 can squeeze additional medicament M out ofthe cartridge body 3510 as illustrated in FIG. 61.

In various embodiments, referring again to FIG. 60, the outer layer 3511can comprise a water impermeable, or at least substantially impermeable,wrap which can configured to, one, keep the medicament from prematurelyflowing out of the staple cartridge 3500 and, two, prevent fluids withina surgical site, for example, from prematurely entering into the staplecartridge 3500. In certain embodiments, the first inner layer 3512 cancomprise a first medicament stored, or absorbed, therein and the secondinner layer 3513 can comprise a second medicament stored, or absorbed,therein, wherein the second medicament can be different than the firstmedicament. In at least one embodiment, an initial compression of thecartridge body 3510, which causes the rupture of the outer layer 3511,can generally express the first medicament out of the first inner layer3512 and a subsequent compression of the cartridge body 3510 cangenerally express the second medicament out of the second inner layer3513. In such embodiments, however, portions of the first medicament andthe second medicament may be expressed simultaneously although amajority of the medicament that is initially expressed can be comprisedof the first medicament and a majority of the medicament subsequentlyexpressed thereafter can be comprised of the second medicament. Incertain embodiments, further to the above, the first inner layer 3512can be comprised of a more compressible material than the second innerlayer 3513 such that the initial compression forces or pressure, whichcan be lower than the subsequent compression forces or pressure, cancause a larger initial deflection within the first inner layer 3512 thanthe second inner layer 3513. This larger initial deflection within thefirst inner layer 3512 can cause a larger portion of the firstmedicament to be expressed from the first inner layer 3512 than thesecond medicament from the second inner layer 3513. In at least oneembodiment, the first inner layer 3512 can be more porous and/or moreflexible than the second inner layer 3513. In at least one suchembodiment, the first inner layer 3512 can comprise a plurality ofpores, or voids, 3508 defined therein and the second inner layer 3513can comprise a plurality of pores, or voids, 3509 defined thereinwherein, in various embodiments, the pores 3508 can be configured tostore the first medicament in the first inner layer 3512 and the pores3509 can be configured to store the second medicament in the secondinner layer 3513. In certain embodiments, the size and density of thepores 3508 within the first inner layer 3512 and the pores 3509 withinthe second inner layer 3513 can be selected so as to provide a desiredresult described herein.

In various embodiments, referring again to FIGS. 60 and 61, the outerlayer 3511, the first inner layer 3512, and/or the second inner layer3513 can be comprised of a bioabsorbable material. In at least oneembodiment, the first inner layer 3512 can be comprised of a firstbioabsorbable material, the second inner layer 3513 can be comprised ofa second bioabsorbable material, and the outer layer 3511 can becomprised of a third bioabsorbable material, wherein the firstbioabsorbable material, the second bioabsorbable material, and/or thethird bioabsorbable material can be comprised of different materials. Incertain embodiments, the first bioabsorbable material can be bioabsorbedat a first rate, the second bioabsorbable material can be bioabsorbed ata second rate, and the third bioabsorbable material can be bioabsorbedat a third rate, wherein the first rate, the second rate, and/or thethird rate can be different. In at least one such embodiment, when amaterial is bioabsorbed at a particular rate, such a rate can be definedas the amount of material mass that is absorbed by a patient's body overa unit of time. As it is known, the bodies of different patients mayabsorb different materials at different rates and, thus, such rates maybe expressed as average rates in order to account for such variability.In any event, a faster rate may be a rate in which more mass isbioabsorbed for a unit of time than a slower rate. In variousembodiments, referring again to FIGS. 60 and 61, the first inner layer3512 and/or the second inner layer 3513 can be comprised of a materialwhich bioabsorbs faster than the material comprising the outer layer3511. In at least one such embodiment, the first inner layer 3512 and/orthe second inner layer 3513 can be comprised of a bioabsorbable foam,tissue sealant, and/or hemostatic material, such as oxidized regeneratedcellulose (ORC), for example, and the outer layer 3511 can be comprisedof a buttress material and/or plastic material, such as polyglycolicacid (PGA) which is marketed under the trade name Vicryl, polylacticacid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA),poliglecaprone 25 (PGCL) which is marketed under the trade nameMonocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS,PHA, PGCL and/or PCL, for example. In such embodiments, the first innerlayer 3512 and/or the second inner layer 3513 can immediately treat thetissue and can reduce bleeding from the tissue, for example, wherein theouter layer 3514 can provide longer-term structural support and can bebioabsorbed at a slower rate.

Owing to the slower rate of bioabsorbability of the outer layer 3511,further to the above, the outer layer 3511 can buttress or structurallyreinforce the tissue within the staple line as it heals. In certainembodiments, one of the first inner layer 3512 and the second innerlayer 3513 can be comprised of a material which can be bioabsorbedfaster than the other such that, in at least one embodiment, one of thelayers can provide an initial release of a therapeutic material and theother layer can provide a sustained release of the same therapeuticmaterial and/or a different therapeutic material. In at least one suchembodiment, the rate in which a therapeutic material can be releasedfrom a layer 3512, 3513 can be a function of the bioabsorbability of thesubstrate layer in which the medicament is absorbed or dispersed. Forexample, in at least one embodiment, the substrate comprising the firstinner layer 3512 can be bioabsorbed faster than the substrate comprisingthe second inner layer 3513 and, as a result, a medicament can berelease from the first inner layer 3512 faster than the second innerlayer 3513, for example. In various embodiments, as described herein,one or more of the layers 3511, 3512, and 3513 of the cartridge body3510 can be adhered to one another by at least one adhesive, such asfibrin and/or protein hydrogel, for example. In certain embodiments, theadhesive can be water soluble and can be configured to release theconnection between the layers as the staple cartridge 3500 is beingimplanted and/or some time thereafter. In at least one such embodiment,the adhesive can be configured to bioabsorb faster than the outer layer3511, the first inner layer 3512, and/or the second inner layer 3513.

In various embodiments, referring now to FIGS. 62 and 63, a staplecartridge, such as staple cartridge 3600, for example, can comprise acartridge body 3610 including a compressible first layer 3611, a secondlayer 3612 attached to the first layer 3611, and a removablecompressible layer 3613 attached to the second layer 3612. In at leastone such embodiment, the first layer 3611 can be comprised of acompressible foam material, the second layer 3612 can comprise alaminate material adhered to the first layer 3611 utilizing one or moreadhesives, and the third layer 3613 can comprise a compressible foammaterial removably adhered to the second layer 3612 utilizing one ormore adhesives, for example. In various embodiments, the staplecartridge 3600 can further comprise a plurality of staples, such asstaples 3620, for example, positioned in the cartridge body 3610. In atleast one such embodiment, each staple 3620 can comprise a base 3622positioned in the third layer 3613 and one or more deformable legs 3621extending upwardly from the base 3622 through the second layer 3612 andinto the first layer 3611, for example. In use, further to the above,the top surface 3619 of the staple cartridge body 3610 can be pusheddownwardly by an anvil until the staple legs 3621 penetrate through thetop surface 3619 and the targeted tissue and contact the anvil. Afterthe staple legs 3621 have been sufficiently deformed, the anvil can bemoved away from the staple cartridge 3600 such that the compressiblelayers thereof can at least partially re-expand. In variouscircumstances, the insertion of the staples through the tissue can causethe tissue to bleed. In at least one embodiment, the third layer 3613can be comprised of an absorbent material, such as protein hydrogel, forexample, which can draw blood away from the stapled tissue. In additionto or in lieu of the above, the third layer 3613 can be comprised of ahemostatic material and/or tissue sealant, such as freeze-dried thrombinand/or fibrin, for example, which can be configured to reduce thebleeding from the tissue. In certain embodiments, the third layer 3613may provide a structural support to the first layer 3611 and the secondlayer 3612 wherein the third layer 3613 may be comprised of abioabsorbable material and/or a non-bioabsorbable material. In anyevent, in various embodiments, the third layer 3613 can be detached fromthe second layer 3612 after the staple cartridge 3610 has beenimplanted. In embodiments where the third layer 3613 comprises animplantable-quality material, the surgeon can elect whether to removethe third layer 3613 of the cartridge body 3610. In at least oneembodiment, the third layer 3613 can be configured to be removed fromthe second layer 3612 in one piece.

In various embodiments, the first layer 3611 can be comprised of a firstfoam material and the third layer 3613 can be comprised of a second foammaterial which can be different than the first foam material. In atleast one embodiment, the first foam material can have a first densityand the second foam material can have a second density wherein the firstdensity can be different than the second density. In at least one suchembodiment, the second density can be higher than the first densitywherein, as a result, the third layer 3613 may be less compressible, orhave a lower compression rate, than the first layer 3611. In at leastone alternative embodiment, the first density can be higher than thesecond density wherein, as a result, the first layer 3611 may be lesscompressible, or have a lower compression rate, than the third layer3613. In various embodiments, referring now to FIGS. 64 and 65, a staplecartridge 3700, similar to the staple cartridge 3600, can comprise acartridge body 3710 comprising a first compressible foam layer 3711, asecond layer 3712 attached to the first layer 3711, and a detachablethird compressible foam layer 3713 removably attached to the secondlayer 3712. In at least one such embodiment, the third layer 3713 cancomprise a plurality of staple receiving slots, or cut-outs, 3709 whichcan each be configured to receive at least a portion of a staple 3620,such as a staple base 3622, for example, therein. In certainembodiments, the staples 3620 can be configured to slide within thestaple receiving slots 3709 or, stated another way, the third layer 3713can be configured to slide relative to the staples 3620 when the staplecartridge 3700 is positioned against the targeted tissue and compressedby an anvil, for example. In at least one embodiment, the receivingslots 3709 can be configured such that there is clearance between thestaples 3620 and the side walls of the receiving slots 3709. In at leastone such embodiment, as a result of the above, the staples 3620 may notcapture a portion of the third layer 3713 therein when the staples 3620are deformed, as illustrated in FIGS. 64 and 65. In certain otherembodiments, the ends of the staple receiving slots 3709 adjacent to thesecond layer 3712 can be closed by a portion of the third layer 3713and, as a result, at least a portion of the third layer 3713 can becaptured within the staples 3620 when they are deformed. In any event,the third layer 3713 can comprise one or more perforations and/or scoremarks 3708, for example, which can be configured to permit the thirdlayer 3713 to be removed from the second layer 3712 in two or morepieces as illustrated in FIG. 64. In FIG. 64, one of the pieces of thethird layer 3713 is illustrated as being removed by a tool 3755. Invarious embodiments, the perforations 3708 can be arranged along a linepositioned intermediate a first row of staples and a second row ofstaples.

In various embodiments, referring again to FIGS. 64 and 65, the bases3622 of the staples 3620 can be positioned within the receiving slots3709 wherein, in at least one embodiment, the side walls of thereceiving slots 3709 can be configured to contact and releasable retainthe staple legs 3621 in position. In certain embodiments, although notillustrated, the third layer 3713 can comprise an elongated slotsurrounding all of the staples within a staple line. In at least onesuch embodiment, a staple cartridge comprising four staple rows, forexample, can comprise an elongate slot aligned with each staple row inthe bottom layer of the staple cartridge. Further to the above, at leasta portion of the staple cartridge 3600 and/or the staple cartridge 3700can be implanted within a patient and at least a portion of the staplecartridge can be removable from the patient. In at least one embodiment,referring again to FIGS. 64 and 65, the first layer 3711 and the secondlayer 3712 can be captured within the staples 3620 and can be implantedwith the staples 3620, whereas the third layer 3713 can be optionallyremoved or detached from the staple cartridge 3700. In variouscircumstances, the removal of a portion of the implanted staplecartridge can reduce the amount of material that the patient's body hasto reabsorb which can provide various therapeutic benefits. In the eventthat a portion of a staple cartridge is detached and removed, such as bya laparoscopic tool 3755, for example, the detached staple cartridgeportion can be removed from the surgical site through a trocar, such asa trocar having a 5 mm aperture, for example. In certain embodiments, acartridge body can comprise more than one layer that can be removed. Forexample, the cartridge body 3710 can comprise a fourth layer wherein thethird layer of 3713 of the cartridge body 3710 can be comprised of ahemostatic material and the fourth layer can be comprised of a supportlayer. In at least one such embodiment, a surgeon can remove the supportlayer and then elect whether to remove the hemostatic layer, forexample.

In various embodiments, referring now to FIG. 66, a staple cartridge,such as staple cartridge 3800, for example, can comprise a cartridgebody 3810 including an outer layer 3811 and an inner layer 3812. Theinner layer 3812 can be comprised of a compressible foam material andthe outer layer 3811 can be at leas partially wrapped around the innerlayer 3812. In at least one embodiment, the outer layer 3811 cancomprise a first portion 3811 a configured to be positioned on a firstside of the inner layer 3812 and a second portion 3811 b configured tobe positioned on a second side of the inner layer 3812 wherein the firstportion 3811 a and the second portion 3811 b can be connected by aflexible hinge, such as hinge 3809, for example. In at least one suchembodiment, at least one adhesive, such as fibrin and/or proteinhydrogel, for example, can be applied to the first side and/or thesecond side of the inner layer 3812 in order to secure the portions ofthe outer layer 3811 thereto. In various embodiments, the outer layer3811 can comprise one or more fastening members extending therefrom. Inat least one such embodiment, the outer layer 3811 can comprise aplurality of deformable legs 3821 extending from one side of the outerlayer 3811 which can be seated in the compressible inner layer 3812. Inat least one such embodiment, the legs 3821 may not protrude from thesecond side of the inner layer 3812 while, in at least one alternativeembodiment, the legs 3821 may at least partially protrude from the innerlayer 3812. When the compressible cartridge body 3810 is compressed, inuse, the legs 3821 can be configured to pierce the inner layer 3812 andthe second portion 3811 b of the outer layer 3811. In certainembodiments, the second portion 3811 b of the outer layer 3811 cancomprise apertures, such as apertures 3808, for example defined thereinwhich can be configured to receive the staple legs 3821. In certainembodiments, at least portions of the staple cartridge 3800 can comprisea knife slot 3803 which can be configured to slidably receive a cuttingmember therein. In at least one such embodiment, the knife slot 3803 maynot extend entirely through the thickness of the cartridge body 3810and, as a result, the cutting member may incise the cartridge body 3810as it is moved relative thereto.

In various embodiments, referring now to FIG. 67, a staple cartridge3900 can comprise, similar to staple cartridge 3800, a cartridge body3910 including an inner layer 3812 and an outer layer 3811, wherein theouter layer 3811 can comprise a first portion 3811 a positioned adjacentto the first side of the inner layer 3812 and a second portion 3811 bpositioned adjacent to the second side of the inner layer 3812. In atleast one embodiment, similar to the above, the outer layer 3811 cancomprise one or more fastening members extending therefrom. In at leastone such embodiment, the outer layer 3811 can comprise a plurality ofdeformable legs 3921 extending from one side of the outer layer 3811which can be seated in the compressible inner layer 3812. In certainembodiments, each deformable leg 3921 can comprise at least one hook orbarb 3923 protruding therefrom which can be configured to engage thesecond portion 3811 b of the outer layer 3811 and, as a result, retainthe outer layer 3811 to the inner layer 3812. In at least one suchembodiment, the barbs 3923 can be configured to protrude from the secondside of the inner layer 3812 and extend through the apertures 3808 inthe second portion 3811 b of the outer layer 3811 such that the barbs3923 can engage the outside surface of the outer layer 3811 and lock theouter layer 3811 to the inner layer 3812. In order to construct thestaple cartridge 3900, the inner layer 3812 may be at least partiallycompressed in order to cause the barbs to protrude therefrom and enterinto the apertures 3808. In at least one such embodiment, the staplecartridge 3900 can be at least partially pre-compressed when it isinserted into a staple cartridge, for example. In certain embodiments,further to the above, at least a portion of the legs 3921 can beembedded within the first portion 3811 a of the outer layer 3811wherein, in at least one embodiment, the outer layer 3811 can becomprised of a plastic material, such as polydioxanone (PDS) and/orpolyglycolic acid (PGA), for example, and the plastic material can beovermolded around at least a portion of the legs 3921.

In various embodiments, referring now to FIGS. 68-72, a staplecartridge, such as staple cartridge 4000, for example, can comprise acartridge body 4010 including a compressible first layer 4011 and asecond layer 4012 and, in addition, a plurality of staples 4020positioned within the cartridge body 4010. In certain embodiments,referring to FIG. 70, each staple 4020 can comprise a base 4022 and atleast one deformable leg 4023 extending from the base 4022. In at leastone embodiment, referring to FIG. 68, the staple cartridge 4000 can bepositioned between a staple cartridge channel 4030 and an anvil 4040 ofan end effector of a surgical stapler wherein the second layer 4012 ofthe cartridge body 4010 and/or the bases 4022 of the staples 4020 can bepositioned against the staple cartridge channel 4030. In variousembodiments, referring now to FIG. 69, the second layer 4012 cancomprise a layer of pledgets 4060 interconnected to one another by apledget support frame 4061. In at least one such embodiment, thepledgets 4060 and the pledget support frame 4061 can be comprised of amolded plastic material, such as polyglycolic acid (PGA), for example.Each pledget 4060 can comprise one or more apertures or slots 4062 whichcan be configured to receive a staple leg 4021 extending therethrough asillustrated in FIGS. 70 and 71. Each pledget 4060 can further comprise areceiving slot 4063 defined therein which can be configured to receive abase 4022 of a staple 4020. In various embodiments, referring again toFIG. 69, the pledgets 4060 and/or pledget support frame 4061 cancomprise a plurality of score marks, perforations, or the like which canbe configured to allow the pledgets 4060 to become detached from thepledget support frame 4061 at a desired location. Similarly, referringto FIG. 71, one or more pledgets 4060 can be connected to one anotheralong a line comprising perforations and/or score marks 4064, forexample. In use, the compressible foam layer 4011 can be positionedagainst the targeted tissue T and the cartridge body 4010 can becompressed by the anvil 4040 such that the anvil 4040 can deform thestaples 4020. When the staples 4020 are deformed, the staple legs 4021of each staple 4020 can capture the tissue T, a portion of the firstlayer 4011, and a pledget 4060 within the deformed staple. When thestaple cartridge channel 4030 is moved away from the implanted staplecartridge 4060, for example, the pledget support frame 4061 can bedetached from the pledgets 4060 and/or the pledgets 4060 can be detachedfrom one another. In certain circumstances, the pledgets 4060 can bedetached from the frame 4061 and/or each other when the staples 4020 arebeing deformed by the anvil 4040 as described above.

In various embodiments described herein, the staples of a staplecartridge can be fully formed by an anvil when the anvil is moved into aclosed position. In various other embodiments, referring now to FIGS.73-76, the staples of a staple cartridge, such as staple cartridge 4100,for example, can be deformed by an anvil when the anvil is moved into aclosed position and, in addition, by a staple driver system which movesthe staples toward the closed anvil. The staple cartridge 4100 cancomprise a compressible cartridge body 4110 which can be comprised of afoam material, for example, and a plurality of staples 4120 at leastpartially positioned within the compressible cartridge body 4110. Invarious embodiments, the staple driver system can comprise a driverholder 4160, a plurality of staple drivers 4162 positioned within thedriver holder 4160, and a staple cartridge pan 4180 which can beconfigured to retain the staple drivers 4162 in the driver holder 4160.In at least one such embodiment, the staple drivers 4162 can bepositioned within one or more slots 4163 in the driver holder 4160wherein the sidewalls of the slots 4163 can assist in guiding the stapledrivers 4162 upwardly toward the anvil. In various embodiments, thestaples 4120 can be supported within the slots 4163 by the stapledrivers 4162 wherein, in at least one embodiment, the staples 4120 canbe entirely positioned in the slots 4163 when the staples 4120 and thestaple drivers 4162 are in their unfired positions. In certain otherembodiments, at least a portion of the staples 4120 can extend upwardlythrough the open ends 4161 of slots 4163 when the staples 4120 andstaple drivers 4162 are in their unfired positions. In at least one suchembodiment, referring primarily now to FIG. 74, the bases of the staples4120 can be positioned within the driver holder 4160 and the tips of thestaples 4120 can be embedded within the compressible cartridge body4110. In certain embodiments, approximately one-third of the height ofthe staples 4120 can be positioned within the driver holder 4160 andapproximately two-thirds of the height of the staples 4120 can bepositioned within the cartridge body 4110. In at least one embodiment,referring to FIG. 73A, the staple cartridge 4100 can further comprise awater impermeable wrap or membrane 4111 surrounding the cartridge body4110 and the driver holder 4160, for example.

In use, the staple cartridge 4100 can be positioned within a staplecartridge channel, for example, and the anvil can be moved toward thestaple cartridge 4100 into a closed position. In various embodiments,the anvil can contact and compress the compressible cartridge body 4110when the anvil is moved into its closed position. In certainembodiments, the anvil may not contact the staples 4120 when the anvilis in its closed position. In certain other embodiments, the anvil maycontact the legs of the staples 4120 and at least partially deform thestaples 4120 when the anvil is moved into its closed position. In eitherevent, the staple cartridge 4100 can further comprise one or more sleds4170 which can be advanced longitudinally within the staple cartridge4100 such that the sleds 4170 can sequentially engage the staple drivers4162 and move the staple drivers 4162 and the staples 4120 toward theanvil. In various embodiments, the sleds 4170 can slide between thestaple cartridge pan 4180 and the staple drivers 4162. In embodimentswhere the closure of the anvil has started the forming process of thestaples 4120, the upward movement of the staples 4120 toward the anvilcan complete the forming process and deform the staples 4120 to theirfully formed, or at least desired, height. In embodiments where theclosure of the anvil has not deformed the staples 4120, the upwardmovement of the staples 4120 toward the anvil can initiate and completethe forming process and deform the staples 4120 to their fully formed,or at least desired, height. In various embodiments, the sleds 4170 canbe advanced from a proximal end of the staple cartridge 4100 to a distalend of the staple cartridge 4100 such that the staples 4120 positionedin the proximal end of the staple cartridge 4100 are fully formed beforethe staples 4120 positioned in the distal end of the staple cartridge4100 are fully formed. In at least one embodiment, referring to FIG. 75,the sleds 4170 can each comprise at least one angled or inclined surface4711 which can be configured to slide underneath the staple drivers 4162and lift the staple drivers 4162 as illustrated in FIG. 76.

In various embodiments, further to the above, the staples 4120 can beformed in order to capture at least a portion of the tissue T and atleast a portion of the compressible cartridge body 4110 of the staplecartridge 4100 therein. After the staples 4120 have been formed, theanvil and the staple cartridge channel 4130 of the surgical stapler canbe moved away from the implanted staple cartridge 4100. In variouscircumstances, the cartridge pan 4180 can be fixedly engaged with thestaple cartridge channel 4130 wherein, as a result, the cartridge pan4180 can become detached from the compressible cartridge body 4110 asthe staple cartridge channel 4130 is pulled away from the implantedcartridge body 4110. In various embodiments, referring again to FIG. 73,the cartridge pan 4180 can comprise opposing side walls 4181 betweenwhich the cartridge body 4110 can be removably positioned. In at leastone such embodiment, the compressible cartridge body 4110 can becompressed between the side walls 4181 such that the cartridge body 4110can be removably retained therebetween during use and releasablydisengaged from the cartridge pan 4180 as the cartridge pan 4180 ispulled away. In at least one such embodiment, the driver holder 4160 canbe connected to the cartridge pan 4180 such that the driver holder 4160,the drivers 4162, and/or the sleds 4170 can remain in the cartridge pan4180 when the cartridge pan 4180 is removed from the surgical site. Incertain other embodiments, the drivers 4162 can be ejected from thedriver holder 4160 and left within the surgical site. In at least onesuch embodiment, the drivers 4162 can be comprised of a bioabsorbablematerial, such as polyglycolic acid (PGA) which is marketed under thetrade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS),polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketedunder the trade name Monocryl, polycaprolactone (PCL), and/or acomposite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. Invarious embodiments, the drivers 4162 can be attached to the staples4120 such that the drivers 4162 are deployed with the staples 4120. Inat least one such embodiment, each driver 4162 can comprise a troughconfigured to receive the bases of the staples 4120, for example,wherein, in at least one embodiment, the troughs can be configured toreceive the staple bases in a press-fit and/or snap-fit manner.

In certain embodiments, further to the above, the driver holder 4160and/or the sleds 4170 can be ejected from the cartridge pan 4180. In atleast one such embodiment, the sleds 4170 can slide between thecartridge pan 4180 and the driver holder 4160 such that, as the sleds4170 are advanced in order to drive the staple drivers 4162 and staples4120 upwardly, the sleds 4170 can move the driver holder 4160 upwardlyout of the cartridge pan 4180 as well. In at least one such embodiment,the driver holder 4160 and/or the sleds 4170 can be comprised of abioabsorbable material, such as polyglycolic acid (PGA) which ismarketed under the trade name Vicryl, polylactic acid (PLA or PLLA),polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25(PGCL) which is marketed under the trade name Monocryl, polycaprolactone(PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, forexample. In various embodiments, the sleds 4170 can be integrally formedand/or attached to a drive bar, or cutting member, which pushes thesleds 4170 through the staple cartridge 4100. In such embodiments, thesleds 4170 may not be ejected from the cartridge pan 4180 and may remainwith the surgical stapler while, in other embodiments in which the sleds4170 are not attached to the drive bar, the sleds 4170 may be left inthe surgical site. In any event, further to the above, thecompressibility of the cartridge body 4110 can allow thicker staplecartridges to be used within an end effector of a surgical stapler asthe cartridge body 4110 can compress, or shrink, when the anvil of thestapler is closed. In certain embodiments, as a result of the staplesbeing at least partially deformed upon the closure of the anvil, tallerstaples, such as staples having an approximately 0.18″ staple height,for example, could be used, wherein approximately 0.12″ of the stapleheight can be positioned within the compressible layer 4110 and whereinthe compressible layer 4110 can have an uncompressed height ofapproximately 0.14″, for example.

In various embodiments, referring now to FIGS. 77-80, a staplecartridge, such as staple cartridge 4200, for example, can comprise acompressible cartridge body 4210, a plurality of staples 4220 positionedtherein, and a plurality of flexible lateral support members 4234. Invarious embodiments, referring now to FIG. 78, the staple cartridge 4200can be positioned intermediate an anvil 4240 and a staple cartridgechannel 4230 wherein, in at least one embodiment, the lateral supportmembers 4234 can be attached to the staple cartridge channel 4230. Whenthe anvil 4240 is moved downwardly to compress the cartridge body 4210and at least partially deform the staples 4220, as illustrated in FIG.79, the side portions of the cartridge body 4210 can bulge laterally andpush the lateral support members 4234 outwardly. In at least one suchembodiment, the lateral support members 4234 can be attached to thecartridge body 4210 and, when the cartridge body 4210 bulges laterallyas described above, the lateral support members 4234 can detach from thecartridge body 4210 as illustrated in FIG. 79. In at least oneembodiment, the lateral support members 4234 can be adhered to thecartridge body 4210 utilizing at least one adhesive, such as fibrinand/or protein hydrogel, for example. Similar to the above, the closingof the anvil 4240 may only partially deform the staples 4220, whereinthe formation of the staples 4220 can be completed by the advancement ofone or more sleds 4270 through the staple cartridge 4200 as illustratedin FIG. 80. In various embodiments, referring now to FIGS. 82 and 83,the sleds 4270 can be advanced from a proximal end of the staplecartridge 4200 to a distal end of the staple cartridge 4200 by a cuttingmember 4280. In at least one such embodiment, the cutting member 4280can comprise a cutting element, or knife, 4283, which can be advancedthrough the tissue T and/or the compressible cartridge body 4210. Incertain embodiments, the cutting member 4280 can comprise cammingmembers 4282 which can travel along the outside surfaces of the jaws4230 and 4240 and move or hold the jaws in position. In variousembodiments, as a result of the above, the staples 4220 can be formedinto their final shapes at the same time, or at least substantially thesame time, as the tissue T is incised. In at least one such embodiment,the sleds 4270 can be positioned distally with respect to the knife 4283such that the tissue T is only incised when the proceeding portion ofthe tissue has been fully stapled, for example.

In various embodiments, referring again to FIGS. 82 and 83, the sleds4270 can comprise separate slidable members which are advanced togetherby the cutting member 4280. In at least one such embodiment, the sleds4270 can be contained within the staple cartridge 4200 and the cuttingmember 4280 can be advanced into the staple cartridge 4200 by a firingbar 4281 such that the cutting member 4280 engages the sleds 4270 andadvances the sleds 4270 distally. In certain embodiments, the sleds 4270can be connected to one another. In either event, each sled 4270 cancomprise an angled surface, or cam, 4271 which can be configured to liftthe staples 4220 aligned within a staple row. In certain embodiments,the angled surfaces 4271 can be integrally formed with the cuttingmember 4280. In at least one embodiment, referring again to FIGS. 82 and83, each staple 4200 can comprise a base, at least one deformable memberextending from the base, and a crown 4229 overmolded onto and/orpositioned around at least a portion of the base and/or the deformablemembers of the staple 4200. In various embodiments, such crowns 4229 canbe configured to be driven directly by a sled 4270, for example. Moreparticularly, in at least one embodiment, the crowns 4229 of staples4220 can be configured such that the angled surfaces 4271 of the sleds4270 can slide underneath and directly contact the crowns 4229 without astaple driver positioned therebetween. In such embodiments, each crown4229 can comprise at least one co-operating angled or inclined surfacewhich can be engaged by an angled surface 4271 of the sleds 4270 suchthat the co-operating angled surfaces can drive the staples 4220upwardly when the sleds 4270 are slid underneath the staples 4220.

In various embodiments, referring now to FIG. 81, a staple cartridge,such as staple cartridge 4300, for example, can comprise a compressiblebody 4310 and a plurality of staples 4320 positioned within thecompressible body 4310. Similar to the above, the staple cartridge 4300can comprise flexible lateral supports 4334 which can be attached to astaple cartridge channel and/or adhered to the compressible body 4310.In addition to the above, the flexible lateral supports 4334 can beconnected together by one or more struts, or connection members, 4335which can be configured to hold the lateral supports 4334 together. Inuse, the connection members 4335 can be configured to prevent, or atleast inhibit, the lateral supports 4334 from becoming prematurelydetached from the cartridge body 4310. In certain embodiments, theconnection members 4335 can be configured to hold the lateral supports4334 together after the staple cartridge 4300 has been compressed by ananvil. In such embodiments, the lateral supports 4334 can resist thelateral bulging, or displacement, of the lateral portions of thecartridge body 4310. In certain embodiments, a cutting member, such ascutting member 4280, for example, can be configured to transect theconnection members 4335 as the cutting member 4280 is moved distallywithin the cartridge body 4310. In at least one such embodiment, thecutting member 4280 can be configured to push one or more sleds, such assleds 4270, for example, distally in order to form the staples 4320against an anvil. The sleds 4270 can lead the cutting edge 4283 suchthat the cutting member 4280 does not transect a connection member 4335until the staples 4320 adjacent to that connection member 4335 have beenfully formed, or at least formed to a desired height. In variouscircumstances, the connection members 4335, in co-operation with thelateral supports 4334, can prevent, or at least reduce, the lateralmovement of the compressible cartridge body 4310 and, concurrently,prevent, or at least reduce, the lateral movement of the staples 4320positioned within the cartridge body 4310. In such circumstances, theconnection members 4335 can hold the staples 4320 in position untilafter they are deformed and the connection members 4335 can bethereafter cut to release the lateral portions of the cartridge body4310. As mentioned above, the lateral supports 4334 can be connected tothe staple cartridge channel and, as a result, can be removed from thesurgical site with the staple cartridge channel after the staplecartridge 4300 has been implanted. In certain embodiments, the lateralsupports 4334 can be comprised of an implantable material and can beleft within a surgical site. In at least one embodiment, the connectionmembers 4335 can be positioned intermediate the cartridge body 4310 andthe tissue T and, after the connection members 4335 have been detachedfrom the lateral supports 4334, the connections members 4335 can remainimplanted in the patient. In at least one such embodiment, theconnection members 4335 can be comprised of an implantable material and,in certain embodiments, the connection members 4335 can be comprised ofthe same material as the lateral supports 4334, for example. In variousembodiments, the connection members 4335 and/or lateral supports 4334can be comprised of a flexible bioabsorbable material such aspolyglycolic acid (PGA) which is marketed under the trade name Vicryl,polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate(PHA), poliglecaprone 25 (PGCL) which is marketed under the trade nameMonocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS,PHA, PGCL and/or PCL, for example. In various embodiments, a connectionmember can comprise a sheet of material connecting the lateral supports4334. In certain embodiments, a staple cartridge can comprise connectionmembers extending across the top surface of the cartridge body 4310 and,in addition, connection members extending around the bottom surface ofthe cartridge body 4310.

In various embodiments, referring now to FIG. 84, a staple cartridge cancomprise staples, such as staples 4420, for example, which can comprisea wire portion inserted into a crown portion. In at least oneembodiment, the wire portion can be comprised of metal, such as titaniumand/or stainless steel, for example, and/or plastic, such aspolydioxanone (PDS) and/or polyglycolic acid (PGA), for example. In atleast one embodiment, the crown portion can be comprised of metal, suchas titanium and/or stainless steel, for example, and/or plastic, such aspolydioxanone (PDS) and/or polyglycolic acid (PGA), for example. Incertain embodiments, the wire portion of each staple 4420 can comprise abase 4422 and deformable legs 4421 extending from the base 4422 whereinthe crown portion of each staple 4420 can comprise a crown 4429 whichcan be configured to receive at least a portion of a base 4422 therein.In order to assemble the portions of each staple 4420, referring now toFIGS. 85A-85C, the legs 4421 of the wire portion can be inserted into anopening 4426 in a crown 4429 wherein the opening 4426 can be configuredto guide the legs 4421 into a base chamber 4427. The wire portion can befurther inserted into the crown 4429 such that the legs 4421 exit thebase chamber 4427 and the base 4422 of the wire portion enters into thebase chamber 4427. In at least one such embodiment, the base chamber4427 can be configured such that the wire portion is rotated within thecrown 4429 as the base 4422 enters into the base chamber 4427 such thatthe staple legs 4421 are pointed in an upward, or at least substantiallyupward, direction. In various embodiments, referring again to FIG. 84,the crown 4429 can comprise exit holes 4425 which can be configured toreceive the staple legs 4421 therein.

In various embodiments, further to the above, a surgical stapler cancomprise a sled 4470 configured to transverse the staple cartridge 4400and staple cartridge channel 4430 and move the staples 4420 containedwithin the cartridge body 4410 toward an anvil. In variouscircumstances, the sled 4470 can be moved from a proximal end of thestaple cartridge channel 4430 to a distal end of the cartridge channel4430 in order to implant the cartridge body 4410 and the staples 4420.In certain circumstances, the sled 4470 can be retracted or returned tothe proximal end of the cartridge channel 4430 and another staplecartridge 4400 can be inserted into the cartridge channel 4430. Once thenew staple cartridge 4400 has been positioned within the cartridgechannel 4430, the sled 4470 can be advanced distally once again. Invarious embodiments, the surgical stapler may comprise one or morelock-out features which can prevent the sled 4470 from being advanceddistally once again without a new staple cartridge 4400 being positionedwithin the cartridge channel 4430. In at least one such embodiment,referring again to FIG. 84, the staple cartridge channel 4430 cancomprise a lock-out shoulder 4439 which can be configured to prevent, orat least limit, the distal movement of the sled 4470. More particularly,the sled 4470 can be configured to abut the shoulder 4439 unless thesled 4470 is at least partially lifted upwardly over the shoulder 4439by a lift feature 4428, for example, extending between the proximal-moststaples 4420 within a staple cartridge 4400. Stated another way, absentthe presence of the proximal-most staples 4420 in a new staple cartridge4400, the sled 4470 cannot be advanced. Thus, when an expended staplecartridge 4400 is present within the cartridge channel 4430, or nostaple cartridge 4400 is present in the cartridge channel 4430 at all,the sled 4470 cannot be advanced within the cartridge channel 4430.

Further to the above, referring now to FIG. 86, a staple cartridge, suchas staple cartridge 4500, for example, can be positioned within a staplecartridge channel 4530 and can comprise a compressible cartridge body4510, a plurality of staples 4520 positioned within the cartridge body4510, and a cartridge pan, or retainer, 4580. In various embodiments,the compressible cartridge body 4510 can comprise an outer layer 4511and an inner layer 4512 wherein, in at least one embodiment, the outerlayer 4511 can sealingly enclose the inner layer 4512. In at least onesuch embodiment, the outer layer 4511 can extend between the inner layer4512 and the cartridge pan 4580. In certain other embodiments, the outerlayer 4511 may only partially surround the inner layer 4512 and, in atleast one such embodiment, the outer layer 4511 and the cartridge pan4580 can co-operate to encompass, or at least substantially encompass,the inner layer 4512. In various embodiments, further to the above, thestaples 4520 can be supported by the cartridge pan 4580 wherein thecartridge pan 4580 can comprise one or more staple support channelsconfigured to support the staples 4520. In certain embodiments, thecartridge pan 4580 can be attached to the cartridge body 4510 wherein,in at least one such embodiment, the cartridge body 4510 can becompressed laterally between opposing side walls of the cartridge pan4580. In various embodiments, the side walls of the cartridge pan 4580can support the cartridge body 4510 laterally and, in at least one suchembodiment, the cartridge pan 4580 can comprise one or more walls, orfins, 4582 extending upwardly from the bottom support 4583 into thecartridge body 4510. In at least one such embodiment, the cartridge body4510 can comprise one or more slots, or channels, therein which can beconfigured to receive and/or interlock with the walls 4582. In variousembodiments, the walls 4582 can extend partially, or almost entirely,through the cartridge body 4510. In at least one such embodiment, thewalls 4582 can extend longitudinally through the staple cartridge 4500between a first row of staples 4520 and a second row of staples 4520.

In various embodiments, the cartridge body 4510 and/or the cartridge pan4580 can comprise co-operating retention features which can provide asnap-fit between the cartridge pan 4580 and the cartridge body 4510. Incertain embodiments, the staple cartridge 4500 can be positioned withinthe cartridge channel 4530 such that the cartridge pan 4580 ispositioned against and/or attached to the cartridge channel 4530. In atleast one embodiment, the cartridge pan 4580 can be detachably coupledto the cartridge channel 4530 such that, after the staple cartridge 4500has been compressed by the anvil 4540 and the staples 4520 have beendeformed, the cartridge pan 4580 can detach from the cartridge channel4530 and can be implanted with the cartridge body 4510. In at least onesuch embodiment, the cartridge pan 4580 can be comprised of abioabsorbable material such as polyglycolic acid (PGA) which is marketedunder the trade name Vicryl, polylactic acid (PLA or PLLA),polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25(PGCL) which is marketed under the trade name Monocryl, polycaprolactone(PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, forexample. In certain embodiments, a surgical stapler can further comprisea firing mechanism and/or driver which can be slid intermediate thestaple cartridge channel 4530 and a bottom drive surface on thecartridge pan 4580 which can be configured to lift or eject thecartridge pan 4580 from the cartridge channel 4530. In certainembodiments, the cartridge body 4510 can be detachably coupled to thecartridge pan 4580 such that, after the staple cartridge 4500 has beencompressed by the anvil 4540 and the staples 4520 have been deformed,the cartridge body 4510 can detach from the cartridge pan 4580. In atleast one such embodiment, the cartridge pan 4580 can remain fixedlyengaged with the cartridge channel 4530 such that the cartridge pan 4580is removed from the surgical site with the cartridge channel 4530. Incertain embodiments, a surgical stapler can further comprise a firingmechanism and/or driver which can be slid intermediate the staplecartridge pan 4580 and a bottom drive surface on the cartridge body 4510which can be configured to lift or eject the cartridge body 4510 fromthe cartridge pan 4580. In at least one such embodiment, the staplecartridge 4500 can further comprise staple drivers positionedintermediate the cartridge pan 4580 and the staples 4520 such that, asthe firing mechanism is slid distally, the staple drivers and thestaples 4520 can be driven upwardly toward the anvil. In at least onesuch embodiment, the staple drivers can be at least partially embeddedwithin the compressible cartridge body 4510.

In various embodiments, similar to the above, the staple cartridge 4500can comprise a lock-out feature which can be configured to prevent, orat least limit, the distal movement of a cutting member unless a unfiredstaple cartridge 4500 has been positioned within the staple cartridgechannel 4530. In certain embodiments, the staple cartridge pan 4580 cancomprise a surface which lifts the cutting member upwardly and over alocking surface within the staple cartridge channel 4530, for example.In the event that a staple cartridge 4500 comprising a cartridge pan4580 is not present in the cartridge channel 4530, the cutting membercannot be advanced. In at least one embodiment, the proximal-moststaples, and/or any other suitable staples, within a staple cartridge4500 can comprise a lifting surface which can sufficiently lift thecutting member over the locking surface. In addition to or in lieu ofthe above, various portions of the staple cartridge 4500 can becomprised of materials having different colors. In such embodiments, asurgeon may be able to visually identify when an unfired and/or firedstaple cartridge is present in the staple cartridge channel 4530. In atleast one such embodiment, the outer layer 4511 of the cartridge body4510 may have a first color, the cartridge pan 4580 may have a secondcolor, and the staple cartridge channel 4530 may have a third color. Inthe event that the surgeon sees the first color, the surgeon may knowthat an unfired cartridge 4500 is present in the staple cartridgechannel 4530; in the event that the surgeon sees the second color, thesurgeon may know that a fired cartridge 4500 is present in the staplecartridge channel 4530 and that the remaining cartridge pan 4580 needsto be removed; and in the event that the surgeon sees the third color,the surgeon may know that no portion of a staple cartridge 4500 remainswithin the cartridge channel 4530.

In various embodiments, referring now to FIG. 87, a staple cartridge,such as staple cartridge 4600, for example, can comprise a compressible,implantable cartridge body 4610 and a plurality of staples 4620positioned therein. The cartridge body 4610 can comprise an outer layer4611 and an inner layer 4612. In certain embodiments, the inner layer4612 can comprise a plurality of pockets, such as pockets, or cavities,4615, for example, defined therein which can facilitate the collapse ofthe cartridge body 4610. In at least one such embodiment, the innerlayer 4612 can comprise a corrugated, or honeycomb-configured, latticewhich can be configured to withstand a compressive force, or pressure,as long as the compressive force, or pressure, does not exceed a certainthreshold value. When the threshold value has not been exceeded, theinner layer 4612 can deform at a linear, or at least substantiallylinear, rate with respect to the compressive force, or pressure, beingapplied. After the compressive force, or pressure, has exceeded thethreshold value, the inner layer 4612 can suddenly succumb to largedeflections and collapse, or buckle, as a result of the compressiveload. In various embodiments, the lattice of the inner layer 4612 can becomprised of a plurality of sub-layers 4612 a which can be connectedtogether. In at least one embodiment, each sub-layer 4612 a can comprisea plurality of alternating furrows and ridges, or waves, which can bealigned with the alternating furrows and ridges of an adjacent sub-layer4612 a. In at least one such embodiment, the furrows of a firstsub-layer 4612 a can be positioned adjacent to the ridges of a secondsub-layer 4612 a and, similarly, the ridges of the first sub-layer 4612a can be positioned adjacent to the furrows of the second sub-layer 4612a. In various embodiments, the adjacent sub-layers 4612 a can be adheredto one another and/or the outer layer 4611 by at least one adhesive,such as fibrin and/or protein hydrogel, for example. FIG. 88 illustratesthe staple cartridge 4600 after the cartridge body 4610 has beencollapsed and the staples 4620 have been deformed in order to captureand hold tissue T against the cartridge body 4610.

In various embodiments, referring now to FIGS. 89-91, a staplecartridge, such as staple cartridge 4700, for example, can comprise acompressible, implantable cartridge body 4710 and a plurality of staples4720 positioned within the cartridge body 4710. Similar to the above,the cartridge body 4710 can comprise an outer layer 4711 and an innerlayer 4712, wherein the inner layer 4712 can comprise a plurality ofsub-layers 4712 a. Also similar to the above, each sub-layer 4712 a cancomprise alternating furrows 4717 and ridges 4718 which can be alignedwith one another to define pockets, or cavities, 4715 therebetween. Inat least one such embodiment, the furrows 4717 and/or the ridges 4718can extend along axes which are parallel to one another and/or parallelto a longitudinal axis 4709. In various embodiments, the staples 4720can be aligned in a plurality of staple rows which can extend along axeswhich are parallel to one another and/or parallel to the longitudinalaxis 4709. In various alternative embodiments, referring again to FIGS.87 and 88, the staples 4620 contained in the cartridge body 4600 canextend along axes which are traverse or perpendicular with respect tothe axes defined by the furrows and ridges of the sub-layers 4612 a.Referring again to FIGS. 89-91, the staples 4720 can extend through thefurrows 4717 and the ridges 4718 wherein friction forces between thestaples 4720 and the sub-layers 4712 a can hold the staples 4720 withinthe cartridge body 4710. In certain embodiments, the plurality ofsub-layers 4712 a can be comprised of a buttress material and/or plasticmaterial, such as polydioxanone (PDS) and/or polyglycolic acid (PGA),for example, which can be configured to hold the staples 4720 in anupright orientation, for example, and/or hold the staples 4720 inalignment with respect to each other as illustrated in FIGS. 89 and 90.FIG. 91 illustrates the staple cartridge 4700 after the cartridge body4710 has been collapsed and the staples 4720 have been deformed in orderto capture and hold tissue T against the cartridge body 4710.

In various embodiments, referring again to FIGS. 89-91, the cartridgebody 4710 can resiliently or elastically collapse when it is compressed.In at least one such embodiment, the waves formed within each sub-layer4712 a by the furrows 4717 and the ridges 4718 can be flattened, or atleast substantially flattened, when the cartridge body 4710 iscompressed which can collapse, or at least substantially collapse, thecavities 4715 defined therebetween. In various circumstances, thecartridge body 4710, or at least portions of the cartridge body 4710,can resiliently or elastically re-expand after the compressive force, orpressure, has been removed from the cartridge body 4710. In at least onesuch embodiment, the connections between the furrows 4717 and the ridges4718 of adjacent sub-layers 4712 a can remain intact, or at leastsubstantially intact, when the cartridge body 4710 is compressed suchthat, after the compression force has been removed from the cartridgebody 4710, the sub-layers 4712 a can bias themselves away from eachother and, as a result, at least partially re-expand the cartridge body4710. In certain embodiments, the cartridge body 4710 can be plasticallydeformed, or crushed, when it is compressed and, as a result, thecartridge body 4710 may not re-expand after the compressive force, orpressure, has been removed from the cartridge body 4710. In certainembodiments, referring now to FIG. 92, a staple cartridge, such asstaple cartridge 4800, for example, can comprise a crushable cartridgebody 4810 comprising an outer layer 4811 and an inner layer 4812,wherein the inner layer 4812 can comprise a corrugated,honeycomb-configured, lattice having a plurality of pockets, orcavities, 4815 defined therein. In various embodiments, the wallsdefining the lattice of inner layer 4812 can comprise one or moreweakened, or thin, cross-sections 4819 which can be configured to allowthe walls defining the lattice to break when the cartridge body 4810 iscompressed. In such circumstances, the cartridge body 4810 can becrushed when the staple cartridge 4800 is implanted.

In various embodiments, referring now to FIGS. 93-95, a staplecartridge, such as staple cartridge 4900, for example, can comprise acartridge body 4910 comprising an outer layer 4911 and a plurality ofcollapsible elements 4912 positioned intermediate top and bottomportions of the outer layer 4911, for example. Referring primarily toFIGS. 93 and 94, the staple cartridge 4900 can further comprise aplurality of staples 4920, wherein each staple 4920 can be positioned ina collapsible element 4912. More particularly, each collapsible element4912 can comprise a first portion 4912 a, a second portion 4012 b, and athird portion 4012 c which can co-operate to define a cavity 4915therein which is configured to receive a staple 4920. In use, further tothe above, the staple cartridge 4900 can be positioned within a staplecartridge channel and a compressive force can be applied to the tissuecontacting surface 4919 in order to compress the cartridge body 4910. Asthe tissue contacting surface 4919 is moved downwardly, the collapsibleelements 4912 can collapse. In such circumstances, the second portion4912 b of each collapsible element 4912 can collapse into acorresponding first portion 4912 a and, similarly, the third portion4912 c of each collapsible element 4912 can collapse into acorresponding second portion 4912 b. As the cartridge body 4910 iscompressed and the collapsible elements 4912 are collapsed, the staples4920 positioned within the collapsible elements 4912 can be deformed, asillustrated in FIG. 95. In various embodiments, the second portion 4912b of each collapsible element 4912 can be frictionally engaged and/orpress-fit within a corresponding first portion 4912 a such that, oncethe compressive force applied to the collapsible element 4912 exceedsthe retention force retaining the first portion 4912 a and the secondportion 4912 b in their extended position (FIG. 94), the first portion4912 a and the second portion 4912 b can begin to slide relative to oneanother. Similarly, the third portion 4912 c of each collapsible element4912 can be frictionally engaged and/or press-fit within a correspondingsecond portion 4912 b such that, once the compressive force applied tothe collapsible element 4912 exceeds the retention force retaining thesecond portion 4912 b and the third portion 4912 c in their extendedposition (FIG. 94), the second portion 4912 b and the third portion 4912c can begin to slide relative to one another.

In many embodiments described herein, a staple cartridge can comprise aplurality of staples therein. In various embodiments, such staples canbe comprised of a metal wire deformed into a substantially U-shapedconfiguration having two staple legs. Other embodiments are envisionedin which staples can comprise different configurations such as two ormore wires that have been joined together having three or more staplelegs. In various embodiments, the wire, or wires, used to form thestaples can comprise a round, or at least substantially round,cross-section. In at least one embodiment, the staple wires can compriseany other suitable cross-section, such as square and/or rectangularcross-sections, for example. In certain embodiments, the staples can becomprised of plastic wires. In at least one embodiment, the staples canbe comprised of plastic-coated metal wires. In various embodiments, acartridge can comprise any suitable type of fastener in addition to orin lieu of staples. In at least one such embodiment, such a fastener cancomprise pivotable arms which are folded when engaged by an anvil. Incertain embodiments, two-part fasteners could be utilized. In at leastone such embodiment, a staple cartridge can comprise a plurality offirst fastener portions and an anvil can comprise a plurality of secondfastener portions which are connected to the first fastener portionswhen the anvil is compressed against the staple cartridge. In certainembodiments, as described above, a sled or driver can be advanced withina staple cartridge in order to complete the forming process of thestaples. In certain embodiments, a sled or driver can be advanced withinan anvil in order to move one or more forming members downwardly intoengagement with the opposing staple cartridge and the staples, orfasteners, positioned therein.

In various embodiments described herein, a staple cartridge can comprisefour rows of staples stored therein. In at least one embodiment, thefour staple rows can be arranged in two inner staple rows and two outerstaple rows. In at least one such embodiment, an inner staple row and anouter staple row can be positioned on a first side of a cutting member,or knife, slot within the staple cartridge and, similarly, an innerstaple row and an outer staple row can be positioned on a second side ofthe cutting member, or knife, slot. In certain embodiments, a staplecartridge may not comprise a cutting member slot; however, such a staplecartridge may comprise a designated portion configured to be incised bya cutting member in lieu of a staple cartridge slot. In variousembodiments, the inner staple rows can be arranged within the staplecartridge such that they are equally, or at least substantially equally,spaced from the cutting member slot. Similarly, the outer staple rowscan be arranged within the staple cartridge such that they are equally,or at least substantially equally, spaced from the cutting member slot.In various embodiments, a staple cartridge can comprise more than orless than four rows of staples stored within a staple cartridge. In atleast one embodiment, a staple cartridge can comprise six rows ofstaples. In at least one such embodiment, the staple cartridge cancomprise three rows of staples on a first side of a cutting member slotand three rows of staples on a second side of the cutting member slot.In certain embodiments, a staple cartridge may comprise an odd number ofstaple rows. For example, a staple cartridge may comprise two rows ofstaples on a first side of a cutting member slot and three rows ofstaples on a second side of the cutting member slot. In variousembodiments, the staple rows can comprise staples having the same, or atleast substantially the same, unformed staple height. In certain otherembodiments, one or more of the staple rows can comprise staples havinga different unformed staple height than the other staples. In at leastone such embodiment, the staples on a first side of a cutting memberslot may have a first unformed height and the staples on a second sideof a cutting member slot may have a second unformed height which isdifferent than the first height, for example.

In various embodiments, referring now to FIGS. 96A-96D, an end effectorof a surgical stapler can comprise a cartridge attachment portion, suchas staple cartridge channel 5030, for example, a fastener cartridgeremovably positioned in the staple cartridge channel 5030, such asstaple cartridge 5000, for example, and a jaw 5040 positioned oppositethe staple cartridge 5000 and the staple cartridge channel 5030. Thestaple cartridge 5000 can comprise a compressible body 5010 and aplurality of staples 5020, and/or any other suitable fasteners, at leastpartially positioned in the compressible body 5010. In at least one suchembodiment, each staple 5020 can comprise a base 5022 and, in addition,legs 5021 extending upwardly from the base 5022, wherein at least aportion of the legs 5021 can be embedded in the cartridge body 5010. Invarious embodiments, the compressible body 5010 can comprise a top, ortissue-contacting, surface 5019 and a bottom surface 5018, wherein thebottom surface 5018 can be positioned against and supported by a supportsurface 5031 of the staple cartridge channel 5030. Similar to the above,the support surface 5031 can comprise a plurality of support slots 5032(FIG. 96D), for example, defined therein which can be configured toreceive and support the bases 5022 of the staples 5020. In variousembodiments, the end effector of the surgical stapler can furthercomprise a retention matrix, such as retention matrix 5050, for example,which can be configured to engage the staples 5020 and capture tissuetherebetween. In at least one such embodiment, the retention matrix 5050can be removably mounted to the jaw 5040. In use, once the staplecartridge 5000 has been positioned within the staple cartridge channel5030, the jaw 5040, and the retention matrix 5050 attached thereto, canbe moved toward the staple cartridge 5000 and the staple cartridgechannel 5030. In at least one embodiment, the jaw 5040 can be moveddownwardly along an axis 5099 such that the jaw 5040 and the staplecartridge channel 5030 remain parallel, or at least substantiallyparallel, to one another as the jaw 5040 is closed. More particularly,in at least one such embodiment, the jaw 5040 can be closed in a mannersuch that a tissue-contacting surface 5051 of the retention matrix 5050is parallel, or at least substantially parallel, to thetissue-contacting surface 5019 of the staple cartridge 5000 as the jaw5040 is moved toward the staple cartridge 5000.

In various embodiments, referring now to FIG. 96A, the retention matrix5050 can be detachably secured to the jaw 5040 such that there islittle, if any, relative movement between the retention matrix 5050 andthe jaw 5040 when the retention matrix 5050 is attached to the jaw 5040.In at least one embodiment, the jaw 5040 can comprise one or moreretention features which can be configured to hold the retention matrix5050 in position. In at least one such embodiment, the retention matrix5050 can be snap-fit and/or press-fit into the jaw 5040. In certainembodiments, the retention matrix 5050 can be adhered to the jaw 5040utilizing at least one adhesive. In any event, the jaw 5040 can be movedinto a position in which the retention matrix 5050 is in contact withthe tissue T and the tissue T is positioned against thetissue-contacting surface 5019 of the staple cartridge 5000. When thetissue T is positioned against the staple cartridge 5000 by the jaw5040, the compressible body 5010 of the staple cartridge 5000 may or maynot be compressed by the jaw 5040. In either circumstance, in variousembodiments, the legs 5021 of the staples 5200 may not protrude throughthe tissue-contacting surface 5019 of the staple cartridge 5000 asillustrated in FIG. 96A. Furthermore, as also illustrated in FIG. 96A,the jaw 5040 can hold the tissue T against the compressible body 5010without engaging the retention matrix 5050 with the staples 5020. Suchembodiments can permit a surgeon to open and close the jaw 5040 multipletimes in order to obtain a desired positioning of the end effectorwithin a surgical site, for example, without damaging the tissue T.Other embodiments are envisioned, however, where the staple tips 5023can protrude from the tissue-contacting surface 5019 prior to thecartridge body 5010 being compressed by the anvil 5040. Once the endeffector has been suitably positioned, referring now to FIG. 96B, thejaw 5040 can be moved downwardly toward the staple cartridge channel5030 such that the compressible body 5010 is compressed by the anvil5040 and such that the tissue-contacting surface 5019 is pusheddownwardly relative to the staples 5020. As the tissue-contactingsurface 5019 is pushed downwardly, the tips 5023 of the staple legs 5021can pierce the tissue-contacting surface 5019 and pierce at least aportion of the tissue T. In such circumstances, the retention matrix5050 may be positioned above the staples 5020 such that the retentionapertures 5052 of retention matrix 5050 are aligned, or at leastsubstantially aligned, with the tips 5023 of the staple legs 5021.

As the retention matrix 5050 is pushed downwardly along the axis 5099,referring now to FIG. 96C, the staple legs 5021 of staples 5020 canenter into the retention apertures 5052. In various embodiments, thestaple legs 5021 can engage the side walls of the retention apertures5052. In certain embodiments, as described in greater detail below, theretention matrix 5050 can comprise one or more retention membersextending into and/or around the retention apertures 5052 which canengage the staple legs 5021. In either event, the staple legs 5021 canbe retained in the retention apertures 5052. In various circumstances,the tips 5023 of the staple legs 5021 can enter into the retentionapertures 5052 and can frictionally engage the retention members and/orthe side walls of the apertures 5052. As the retention matrix 5050 ispushed toward the bases 5022 of the staples 5020, the staple legs 5021can slide relative to the side walls and/or the retention members. As aresult of the above, sliding friction forces can be created between thestaple legs 5021 and the retention matrix 5050 wherein such slidingfriction forces can resist the insertion of the retention matrix 5050onto the staples 5020. In various embodiments, the sliding frictionforces between the retention matrix 5050 and the staples 5020 can beconstant, or at least substantially constant, as the retention matrix5050 is slid downwardly along the staple legs 5021 of the staples 5020.In certain embodiments, the sliding friction forces may increase and/ordecrease as the retention matrix 5050 is slid downwardly along thestaple legs 5021 owing to variations in geometry of the staple legs5021, the retention apertures 5052, and/or the retention membersextending into and/or around the retention apertures 5052, for example.In various embodiments, the insertion of the retention matrix 5050 ontothe staples 5020 can also be resisted by the compressible body 5010 ofthe staple cartridge 5000. More particularly, the compressible body 5010can be comprised of an elastic material, for example, which can apply aresistive force to the retention matrix 5050 which increases as thedistance in which the compressible body 5010 is compressed increases. Inat least one such embodiment, the increase in the resistive forcegenerated by the cartridge body 5010 can be linearly proportional, or atleast substantially linearly proportional, with respect to the distancein which the cartridge body 5010 is compressed. In certain embodiments,the increase in the resistive force generated by the cartridge body 5010can be geometrically proportional with respect to the distance in whichthe cartridge body 5010 is compressed.

In various embodiments, further to the above, a sufficient firing forcecan be applied to the jaw 5040 and the retention matrix 5050 in order toovercome the resistive and friction forces described above. In use, theretention matrix 5050 can be seated to any suitable depth with respectto the staples 5020. In at least one embodiment, the retention matrix5050 can be seated to a depth with respect to the bases 5022 of thestaples 5020 in order to secure two or more layers of tissue togetherand generate compressive forces, or pressure, within the tissue. Invarious circumstances, the system comprising the retention matrix 5050and the staples 5020 can allow a surgeon to select the amount ofcompressive forces, or pressure, that is applied the tissue by selectingthe depth in which the retention matrix 5050 is seated. For example, theretention matrix 5050 can be pushed downwardly toward the staple bases5022 of the staples 5020 until the retention matrix 5050 is seated acertain depth 5011 away from the bottom of the support slots 5032,wherein a shorter depth 5011 can result in higher compressive forces, orpressure, being applied to the tissue T than a taller depth 5011 whichcan result in lower compressive forces, or pressure, being applied tothe tissue T. In various embodiments, the compressive forces, orpressures, applied to the tissue T can be linearly proportional, or atleast substantially linearly proportional, to the depth 5011 in whichthe retention matrix 5050 is seated. In various circumstances, thecompressive forces, or pressure, applied to the tissue T can depend onthe thickness of the tissue T positioned between the retention matrix5050 and the staple cartridge 5020. More particularly, for a givendistance 5011, the presence of thicker tissue T can result in highercompression forces, or pressure, than the presence of thinner tissue T.

In various circumstances, further to the above, a surgeon can adjust thedepth in which the retention matrix 5050 is seated in order to accountfor thicker and/or thinner tissue positioned within the end effector andto apply a certain or predetermined pressure to the tissue T regardlessof the tissue thickness. For example, the surgeon can seat the retentionmatrix 5050 to a shorter depth 5011 when fastening thinner tissue T or ataller depth 5011 when fastening thicker tissue T in order to arrive atthe same, or at least substantially the same, compression pressurewithin the tissue. In certain embodiments, further to the above, asurgeon can selectively determine the amount of compressive pressure toapply to the tissue T positioned between the retention matrix 5050 andthe staple cartridge 5010. In various circumstances, a surgeon canengage the retention matrix 5050 with the staples 5020 and position theretention matrix 5050 a first distance away from the bases 5022 of thestaples 5020 in order to apply a first compressive pressure to thetissue. The surgeon can alternatively position the retention matrix 5050a second distance away from the bases 5022, which is shorter than thefirst distance, in order to apply a second compressive pressure to thetissue which is greater than the first pressure. The surgeon canalternatively position the retention matrix 5050 a third distance awayfrom the bases 5022, which is shorter than the second distance, in orderto apply a third compressive pressure to the tissue which is greaterthan the second pressure. In various embodiments, the fastening systemcomprising the retention matrix 5050 and the staples 5020 can beconfigured to permit a surgeon to apply a wide range of compressivepressures to the targeted tissue.

In various embodiments, referring now to FIG. 96D, the staple legs 5021can be inserted through the retention matrix 5050 such that the stapleleg tips 5023 extend above the top surface of the retention matrix 5050.In at least one embodiment, referring again to FIG. 96C, the jaw 5040can further comprise clearance apertures 5042 defined therein which canbe configured to receive the staple leg tips 5023 as they pass throughthe retention apertures 5052 in the retention matrix 5050. In at leastone such embodiment, the clearance apertures 5042 can be aligned withthe retention apertures 5052 such that the legs 5021 do not contact thejaw 5040. In various embodiments, the clearance apertures 5042 can havea sufficient depth such that the staple legs 5021 do not contact the jaw5040 regardless of the distance in which the retention matrix 5050 isseated. After the retention matrix 5050 has been engaged with thestaples 5020 and seated to a desired position, referring now to FIG.96D, the staple cartridge channel 5030 and the jaw 5040 can be movedaway from the tissue T. More particularly, the staple cartridge channel5030 can be detached from the implanted staple cartridge 5000 and theanvil 5040 can be detached from the implanted retention matrix 5050. Asthe jaw 5040 is moved away from the retention matrix 5050 and the staplesupports 5032 are moved away from the staple bases 5022, the distance5011 between the retention matrix 5050 and the bottom of the bases 5022can be maintained eventhough the jaw 5040 and the staple cartridgechannel 5030 are no longer providing support thereto. In variousembodiments, the static friction forces between the staple legs 5021 andthe retention matrix 5050 can be sufficient to maintain the retentionmatrix 5050 in position despite a biasing force being applied to theretention matrix 5050 by the compressed cartridge body 5010 and/or thecompressed tissue T. In at least one such embodiment, the cartridge body5010 can be comprised of a resilient material which, when compressed,can apply an elastic biasing force to the retention matrix 5050 and thestaples 5020 in a manner which tends to push the retention matrix 5050and the staples 5020 apart, although such movement is opposed by thefrictional engagement between the staple legs 5021 and the retentionmatrix 5050.

In various embodiments, as described above, a retention matrix cancomprise a plurality of retention apertures, wherein each retentionaperture can be configured to receive a leg of a fastener therein. In atleast one embodiment, referring now to FIG. 97, a portion of a retentionmatrix 5150 is illustrated therein which can comprise a retentionaperture 5152 defined by a perimeter 5156. In various embodiments, theperimeter 5156 of the aperture 5152 can comprise a circular, or at leastsubstantially circular, profile and/or any other suitable profile. Incertain embodiments, the retention matrix 5150 can comprise one or moreretention members, such as retention members 5153, for example, whichextend into the aperture 5152 and can be configured to engage a fastenerleg when the fastener leg is inserted therethrough. In at least one suchembodiment, each retention member 5153 can comprise a cantilever whichextends inwardly toward a center axis 5159, i.e., toward the center ofthe aperture 5152. In various embodiments, each cantilever can comprisea first end which is attached to the retention matrix body 5158 and asecond end which forms the perimeter 5156 of the retention aperture5152. In certain embodiments, the perimeter 5156 of a retention aperture5152 can be defined by a first diameter, or width, and a fastener legcan be defined by a second diameter, or width, wherein the seconddiameter can be larger than the first diameter. In at least one suchembodiment, the fastener leg can be configured to contact and deflectone or more of the retention members 5153 in order to increase thediameter of the retention aperture 5152 as the fastener leg is beinginserted therethrough. In certain embodiments, further to the above, thefastener leg can define a perimeter which is larger than the perimeter5156 of the retention aperture 5152 such that the fastener leg canexpand the perimeter 5156 when the fastener leg is inserted therein.

In various embodiments, referring again to FIG. 97, the aperture 5152can be defined by the deformable members 5153, wherein each deformablemember 5153 can be configured to deflect relative to, or independentlyof, the other deformable members 5153. In at least one such embodiment,adjacent deformable members 5153 can be separated by slots 5154 whichcan be configured to permit each deformable member 5153 to flex relativeto the others. In certain embodiments, each slot 5154 can comprise afirst end 5155 in the retention matrix body 5158, a second end openinginto the retention aperture 5152, and a constant, or at leastsubstantially constant, width extending between the first end 5155 andthe second end. In various other embodiments, the width of each slot5154 may not be constant and each slot 5154 may increase and/or decreasein width between the first and second ends thereof. In certainembodiments, the first ends 5155 of the slots 5154 can comprise anenlarged portion, such as a circular portion, which can provide, one,strain relief to the bases of the deformable members 5153 attached tothe retention matrix body 5158 and, two, means for increasing theflexibility of the deformable members 5153. In various embodiments, thegeometry of the deformable members 5153, and/or slots 5154, can beselected so as to provide the deformable members 5153 with a desiredflexibility. In certain embodiments, for example, the slots 5154 can belengthened in order to create longer deformable members 5153 which canbe more flexible than deformable members 5153 having a shorter length.In at least one embodiment, the width of each deformable member 5153 canbe selected so as to provide a desired flexibility thereof. Moreparticularly, deformable members having a thinner width can be moreflexible than deformable members having a thicker width. In certainembodiments, referring again to FIG. 97, the first ends of thecantilevers of deformable members 5153 attached to the retention matrixbody 5158 can be wider than the second ends of the cantilevers. In atleast one such embodiment, the cantilevers can be tapered in a linear,or at least substantially linear, manner between the first and secondends thereof.

In various embodiments, referring again to FIG. 97, the retention matrixbody 5158 can comprise a flat, or at least substantially flat, sheet ofmaterial having a tissue-contacting surface 5151 and a top surface 5157.In at least one such embodiment, the tissue-contacting surface 5151 andthe top surface 5157 can be parallel, or at least substantiallyparallel, to one another. In various embodiments, each deformable member5153 can comprise a first portion 5153 a and a second portion 5153 b,wherein the first portion 5153 a can extend in a first direction and thesecond portion 5153 b can extend in a different, or second, direction.In at least one such embodiment, the retention matrix body 5158 candefine a plane and the first portions 5153 a of the deformable members5153 can lie within such a plane. In various embodiments, the secondportions 5153 b of the deformable members 5153 can extend at an anglerelative to the first portions 5153 a. In at least one such embodiment,the second portions 5153 b can extend in directions which are pointedaway from the top surface 5157 of the retention matrix body 5158 and, incertain embodiments, the second portions 5153 b can converge toward thecentral axis 5159 of the retention aperture 5152. In any event, invarious embodiments, the second portions 5153 b can be configured todeflect away from the central axis 5159 when the fastener leg isinserted therethrough. In embodiments where a staple leg 5021 of astaple 5020 is inserted into a retention aperture 5152, the deformablemembers 5153 can deform in a direction which is generally away from thebases 5122 of the staples 5120. In certain embodiments, as a result, thedeformable members 5153 can deflect in a general direction which is thesame as, or at least substantially the same as, the direction in whichthe staple legs 5021 are being inserted.

In various embodiments, referring again to FIG. BD, the second portions5153 b of the deformable members 5153 can each comprise a sharp tip, forexample, which can be configured to slide against a staple leg 5021 asthe staple leg 5021 is inserted therein. The sharp tips of the secondportions 5153 b can also be configured to bite into the staple leg 5021in the event that the staple leg 5021 were to be pulled in the oppositedirection, i.e., in a direction which would remove the staple leg 5021from the retention aperture 5052. In certain circumstances, the secondportions 5153 b can be inclined at an angle relative to the side of thestaple leg 5021 which is greater than 90 degrees and, as a result, thesecond portions 5153 b may dig, or burrow, into the side of the stapleleg 5021 when the staple leg 5021 experiences a force which tends towithdraw the staple leg 5021 from the retention aperture 5052. Incertain embodiments, the staple legs 5021 can comprise indentationsand/or concavities, such as microindentations, for example, in thesurfaces thereof which can be configured to receive the tips of thedeformable members 5053, for example, therein. In at least one suchembodiment, the tips of the deformable members 5053 can catch in andburrow into the indentations in the staple legs 5021 when a withdrawingforce is applied to the staple legs 5021. In various embodiments, as aresult of the burrowing of the second portions 5153 b into the staplelegs 5021, forces acting to remove the staple legs 5021 from theretention apertures 5022 may only seat the second portions 5153 b deeperinto the staple legs 5021 and increase the force required to remove thestaple legs 5021. Furthermore, owing to the upward inclination of thesecond portions 5153 b, in at least one embodiment, the second portions5153 b can be more permissive to the insertion of a staple leg 5021within a retention aperture 5152 and more resistive to withdrawal of thestaple leg 5021. In at least one embodiment, as a result, the forcerequired to insert a staple leg 5021 into a retention aperture 5022 maybe less than the force required to remove the staple leg 5021 from theretention aperture 5022. In various embodiments, the force needed toremove the staple leg 5021 from the retention aperture 5022 can beapproximately 50 percent greater than the force needed to insert thestaple leg 5021 into the retention aperture 5022, for example. Invarious other embodiments, the force needed to remove the staple leg5021 may between approximately 10 percent and approximately 100 percentgreater than the force needed to insert the staple leg 5021, forexample. In certain embodiments, the force needed to remove the stapleleg 5021 may be approximately 100 percent, approximately 150 percent,approximately 200 percent, and/or greater than approximately 200 percentlarger than the force needed to insert the staple leg 5021, for example.

In certain embodiments, referring again to FIG. 97, the second portions5153 b can be arranged circumferentially around the aperture 5152 andcan define a pocket therebetween. More particularly, the second portions5153 b can define a pocket 5160 which can be configured to receive thetip of the fastener leg when it is inserted into the retention aperture5152. In various embodiments, the second portions 5153 b of thedeformable members 5153 can comprise an annular, or an at leastsubstantially annular, contour which can co-operatively define anannular, or at least substantially annular, profile of the pocket 1560,for example. In at least one such embodiment, the second portions 5153 bcan define a conical or frustoconical pocket. In various embodiments,the pocket can be defined by a suitable number of deformable members,such as four deformable members 5153 (FIG. 97), six deformable members5153 (FIG. 98), or eight deformable members 5153 (FIG. 99), for example.In certain embodiments, referring now to FIG. 100, the deformablemembers of a retention matrix, such as retention matrix 5250, forexample, can form a pyramidal shape, or an at least substantiallypyramidal shape, for example. In various embodiments, a retention matrix5250 can comprise a plurality of retention apertures, such as retentionaperture 5252, for example, which can be defined by a perimeter 5256. Invarious embodiments, the perimeter 5256 can comprise a polygonal, or atleast substantially polygonal, profile and/or any other suitableprofile. In certain embodiments, the retention matrix 5250 can compriseone or more retention members, such as retention members 5253, forexample, which extend into the aperture 5252 and can be configured toengage a fastener leg when the fastener leg is inserted therethrough. Inat least one such embodiment, each retention member 5253 can comprise acantilever which extends inwardly toward a center axis 5259, i.e.,toward the center of the aperture 5252. In various embodiments, eachcantilever can comprise a first end which is attached to the retentionmatrix body 5258 and a second end which forms the perimeter 5256 of theretention aperture 5252. In certain embodiments, the perimeter 5256 of aretention aperture 5252 can be defined by a first diameter, or width,and a fastener leg can be defined by a second diameter, or width,wherein the second diameter can be larger than the first diameter. In atleast one such embodiment, the fastener leg can be configured to contactand deflect one or more of the retention members 5253 in order toincrease the diameter of the retention aperture 5252 as the fastener legis being inserted therethrough. In certain embodiments, further to theabove, the fastener leg can define a perimeter which is larger than theperimeter 5256 of the retention aperture 5252 such that the fastener legcan expand the perimeter 5256 when the fastener leg is inserted therein.

In various embodiments, referring again to FIG. 100, the aperture 5252can be defined by the deformable members 5253, wherein each deformablemember 5253 can be configured to deflect relative to, or independentlyof, the other deformable members 5253. In at least one such embodiment,adjacent deformable members 5253 can be separated by slots 5254 whichcan be configured to permit each deformable member 5253 to flex relativeto the others. In various embodiments, the retention matrix body 5258can comprise a flat, or at least substantially flat, sheet of materialhaving a tissue-contacting surface 5251 and a top surface 5257. In atleast one such embodiment, the tissue-contacting surface 5251 and thetop surface 5257 can be parallel, or at least substantially parallel, toone another. In various embodiments, each deformable member 5253 cancomprise a first portion 5253 a and a second portion 5253 b, wherein thefirst portion 5253 a can extend in a first direction and the secondportion 5253 b can extend in a different, or second, direction. In atleast one such embodiment, the retention matrix body 5258 can define aplane and the first portions 5253 a of the deformable members 5253 canlie within such a plane. In various embodiments, the second portions5253 b of the deformable members 5253 can extend at an angle relative tothe first portions 5253 a. In at least one such embodiment, the secondportions 5253 b can extend in directions which are pointed away from thetop surface 5257 of the retention matrix body 5258 and, in certainembodiments, the second portions 5253 b can converge toward the centralaxis 5259 of the retention aperture 5252. In any event, in variousembodiments, the second portions 5253 b can be configured to deflectaway from the central axis 5259 when the fastener leg is insertedtherethrough. In certain embodiments, referring again to FIG. 100, thesecond portions 5253 b can be arranged circumferentially around theaperture 5252 and can define a pocket therebetween. More particularly,the second portions 5253 b can define a pocket which can be configuredto receive the tip of the fastener leg when it is inserted into theretention aperture 5252. In various embodiments, the second portions5253 b of the deformable members 5253 can define a polygonal, or an atleast substantially polygonal, pocket, for example. In variousembodiments, the pocket can be defined by a suitable number ofdeformable members, such as four deformable members 5253 (FIG. 100)which can define a square, six deformable members 5253 (FIG. 101) whichcan define a hexagon, or eight deformable members 5253 (FIG. 102) whichcan define an octagon, for example.

In various embodiments, referring now to FIG. 103, a retention matrix,such as retention matrix 5350, for example, can be formed from a flat,or an at least substantially flat, sheet of material such as titaniumand/or stainless steel, for example. In at least one such embodiment, aplurality of apertures 5352 can be formed in the body 5358 of theretention matrix 5350 by one or more stamping processes. The sheet ofmaterial can be positioned in a stamping die which, when actuated, canpunch out certain portions of the material in order to form slots 5354,apertures 5355 of slots 5354, and/or the perimeter 5356 of the retentionaperture 5352, for example. The stamping die can also be configured tobend the deformable members 5353 in a suitable configuration. In atleast one such embodiment, the stamping die can deform the secondportions 5353 b upwardly relative to the first portions 5353 a along acrease line 5353 c. In various embodiments, referring now to FIG. 104, aretention matrix, such as retention matrix 5450, for example, cancomprise a plurality of retention apertures 5452. Similar to the above,the perimeter 5456 of each retention aperture 5452 can be defined by aplurality of deformable members 5453 separated by slots, or slits, 5454.In at least one such embodiment, the entirety of each deformable member5453 can be bent upwardly wherein the free ends of the cantileverscomprising the deformable members 5453 can define the perimeter 5456. Invarious embodiments, the retention matrix 5450 can comprise a pluralityof apertures 5455 surrounding, or at least substantially surrounding,the retention aperture 5452. In at least one such embodiment, theapertures 5455 can be arranged in a circular array surrounding orenclosing a perimeter defined by the fixed ends of the cantilevers ofthe deformable members 5453. In certain embodiments, each aperture 5455can comprise a circular, or at least substantially circular, perimeterand/or any other suitable perimeter. In use, the apertures 5455 canprovide, one, strain relief to the bases of the deformable members 5453attached to the retention matrix body 5458 and, two, means forincreasing the flexibility of the deformable members 5453. In variousembodiments, larger apertures 5455 can provide more flexibility to thedeformable members 5453 as compared to smaller apertures 5455.Furthermore, apertures 5455 which are closer to the deformable members5453 can provide more flexibility as compared to apertures 5455 whichare further away.

In various embodiments, referring now to FIG. 105, a retention matrix,such as retention matrix 5550, for example, can comprise a plurality ofretention apertures 5552. Each retention aperture 5552 can comprise anelongate slot 5554 having enlarged circular, or at least substantiallycircular, ends 5555. In at least one such embodiment, the ends 5555 canbe defined by a diameter which is wider than the slot 5554. In certainembodiments, the elongate slot 5554 and the ends 5555 can positionedalong, and/or centered along, a longitudinal axis 5559. In variousembodiments, the slot 5554 and the ends 5555 can define two opposingtabs 5553 which can be configured to engage a leg of a fastener anddeflect as the fastener leg is inserted therethrough. In at least oneembodiment, ends 5555 having a larger perimeter, or diameter, can definelonger tabs 5553 which can be more flexible than tabs 5553 defined byends 5555 having a smaller perimeter, or diameter. In variousembodiments, the ends 5555 can have the same perimeter and diameter and,in at least one such embodiment, each tab 5553 can be symmetrical aboutan axis which is perpendicular, or at least substantially perpendicular,to the longitudinal axis 5559. Alternatively, the ends 5555 can havedifferent perimeters and/or diameters wherein, in at least oneembodiment, each tab 5553 may not be symmetrical about its axis. In atleast one such alternative embodiment, the tabs 5553 may twist abouttheir axes as the fastener leg is inserted through the retentionaperture 5552. In various embodiments, referring now to FIG. 106, aretention matrix, such as retention matrix 5650, for example, cancomprise a plurality of retention apertures 5652. Each retentionaperture 5652 can comprise an elongate slot 5654 comprising circular, orat least substantially circular, ends 5655. In at least one suchembodiment, the elongate slot 5654 and the ends 5655 can be positionedalong, and/or centered along, a longitudinal axis 5659. In variousembodiments, each end 5655 can be defined by a diameter which is thesame as, or at least substantially the same as, the width of the slot5654.

In various embodiments, referring now to FIG. 107, a retention matrix,such as retention matrix 5750, for example, can comprise a plurality ofretention apertures 5752. Each retention aperture 5752 can comprise aplurality of slots, such as slots 5754, for example, having enlargedends 5755. In at least one such embodiment, the slots 5754 and the ends5755 can be positioned along and/or centered along longitudinal axes5759. In various embodiments, the axes 5759 can extend in directionswhich are perpendicular or transverse to one another. In certainembodiments, the slots 5754 and the ends 5755 can define four tabs 5753,for example, which can be configured to engage a fastener leg anddeflect when the fastener leg is inserted through the retention aperture5752. In at least one embodiment, each tab 5753 can comprise atriangular, or at least substantially triangular, configuration, such asan equilateral triangle, for example. In various other embodiments,referring now to FIG. 108, a retention matrix, such as retention matrix5850, for example, can comprise a plurality of retention apertures 5852.Each retention aperture 5852 can comprise a plurality of slots, such asslots 5854, for example, having ends 5855, wherein the slots 5854 andthe ends 5855 can be positioned along and/or centered along longitudinalaxes 5859. In various embodiments, the axes 5859 can extend indirections which are perpendicular or transverse to one another. Incertain embodiments, the slots 5854 and the ends 5855 can define tabs5853 which can be configured to engage a fastener leg and deflect whenthe fastener leg is inserted through the retention aperture 5852. In atleast one embodiment, each tab 5853 can comprise an arcuate profile.More particularly, each tab 5853 can comprise a curved end, as opposedto a pointed end depicted in FIG. 105, which can be configured tocontact the fastener leg.

In various embodiments, referring now to FIG. 109, a retention matrix,such as retention matrix 5950, for example, can comprise a plurality ofretention apertures 5952. Each retention aperture 5952 can comprise aplurality of slots, such as slots 5954, for example, wherein each slot5954 can extend along, and/or can be centered along, an axis 5959. Invarious embodiments, the axes 5959 can be transverse to each other and,in at least one such embodiment, the axes 5959 can be arranged such thatall of the axes 5959 extend through a center of the retention aperture5952 and are spaced equidistantly, or at least substantiallyequidistantly, from each other. In at least one embodiment, each slot5954 can comprise an open end facing the center of the retentionaperture 5952 and a second, or closed, end 5955 at the opposite end ofthe slot 5954. Similar to the above, the slots 5954 and the ends 5955can define three tabs 5953, for example, which can be configured toengage a fastener leg and deflect when the fastener leg is inserted intothe retention aperture 5952. In various embodiments, each tab 5953 cancomprise an arcuate configuration extending between adjacent ends 5955of the slots 5954. In various embodiments, referring now to FIG. 110, aretention matrix, such as retention matrix 6050, for example, cancomprise a plurality of retention apertures 6052. Each retentionaperture 6052 can comprise a tab 6053 which can be configured to engagea fastener leg and to deflect when the fastener leg is inserted into theretention aperture 6052. In at least one such embodiment, the tab 6053can comprise a base fixed to the retention matrix body 6058 and a freeend comprising an arcuate or curved profile 6056 which can be configuredto contact the fastener leg. In certain embodiments, the fastener legcan be a staple leg comprised of a round wire wherein the curved profile6056 can be configured to match, or at least substantially match, acurved outer surface of the round wire.

In various embodiments, referring again to FIG. 110, the retentionmatrix body 6058 can comprise a plurality of slots 6054 and apertures6055 which can be configured to define the tab 6053 and various portionsof the retention aperture 6052. In at least one embodiment, the tab 6053can comprise a rectangular configuration comprising parallel, or atleast substantially parallel, sides. In certain embodiments, referringnow to FIG. 111, a retention matrix, such as retention matrix 6150, forexample, can comprise a plurality of retention apertures 6152. Eachretention aperture 6152 can comprise a tab 6153 which can be configuredto engage a fastener leg and to deflect when the fastener leg isinserted into the retention aperture 6152. In at least one suchembodiment, the tab 6153 can comprise a base fixed to the retentionmatrix body 6158 and a free end comprising an arcuate or curved profile6156 which can be configured to contact the fastener leg. In variousembodiments, the retention matrix body 6158 can comprise a plurality ofslots 6154 and apertures 6155 which can be configured to define the tab6153 and various portions of the retention aperture 6152. In at leastone embodiment, the tab 6153 can comprise a tapered configurationcomprising arcuate sides. In at least one such embodiment, the tab 6153can taper geometrically with the base being wider than the free end, forexample.

In various embodiments, as described above, a fastening system cancomprise a plurality of staples comprising staple legs which areinserted through a plurality of retention apertures in a retentionmatrix. In certain embodiments, as described in greater detail below,the staples can be held in a first jaw and the retention matrix can beheld in a second jaw, wherein at least one of the first jaw and thesecond jaw can be moved toward the other. In various circumstances, thestaples positioned within the first jaw can be secured therein such thatthe staple legs are aligned with the retention apertures when theretention matrix is engaged with the staple legs. In certainembodiments, referring to FIGS. 112 and 113, a fastener system cancomprise a staple cartridge 6200, for example, positioned in a first jawof a surgical stapler and a retention matrix 6250, for example,positioned in a second jaw of the surgical stapler. Referring now toFIGS. 119 and 120, further to the above, the retention matrix 6250 cancomprise a plurality of retention apertures 6252, wherein each retentionaperture 6252 can comprise a perimeter 6256 defined by one or moredeflectable members 6253. In at least one such embodiment, further tothe above, the deflectable members 6253 defining each aperture 6252 candefine a pocket 6201. In various embodiments, each pocket 6201 cancomprise a curved and/or concave surface, for example, which can beconfigured to guide a tip of a staple leg into the aperture 6252 in theevent that the staple leg is misaligned with the retention aperture 6252and initially contacts the deflectable members 6253 and/or thetissue-contacting surface 6251, for example.

In various embodiments, further to the above, the fastening system canfurther comprise a plurality of staples 6220 comprising staple legs 6221which can be inserted through the retention apertures 6252 in theretention matrix 6250. In at least one such embodiment, each staple 6220can comprise a substantially U-shaped configuration, for example,comprising a base 6222 from which the staple legs 6221 can extendupwardly. In various embodiments, referring now to FIGS. 115 and 116,the retention apertures 6252 in the retention matrix 6250 can bearranged in two parallel, or at least substantially parallel,longitudinal rows, for example, which can extend along, or parallel to,a longitudinal axis of the retention matrix. In certain embodiments, theretention apertures 6252 in a first row can be offset, or staggered,with respect to the retention apertures 6252 in a second row. In atleast one such embodiment, each staple 6220 can comprise a first stapleleg 6221 positioned in a retention aperture 6252 in the first row of anda second staple leg 6221 positioned in a retention aperture 6252 in thesecond row wherein, as a result, the bases 6222 can extend in adirection which is transverse to the longitudinal axis of the retentionmatrix 6250. In at least one such embodiment, the staples 6220 can beparallel, or at least substantially parallel, to one another. Moreparticularly, a base 6222 a of a staple 6220 a be parallel to, or atleast substantially parallel to, a base 6222 b of a staple 6220 b whichcan be parallel to, or at least substantially parallel to, a base 6222 cof a staple 6220 c, for example. In at least one embodiment, the staplelegs 6221 a of staple 6220 a can define a plane which is parallel to, orat least substantially parallel to, a plane defined by the staple legs6221 b of staple 6220 b which can be parallel to, or at leastsubstantially parallel to, a plane defined by the staple legs 6221 ofstaple 6220 c, for example.

In various embodiments, referring now to FIGS. 112 and 114, the staplecartridge 6200 can comprise a plurality of staples 6220 and, inaddition, an alignment matrix 6260 comprising a plurality of alignmentguides, such as slots, grooves, and/or apertures, for example, which canbe configured to align the staples 6220. In various circumstances, thealignment matrix 6260 can be configured such that the staple legs 6221of the staples 6220 are aligned with the retention apertures 6252 in theretention matrix 6250 before the retention matrix 6250 is engaged withthe staple legs 6221. In various embodiments, referring now to FIGS. 117and 118, the alignment matrix 6260 can comprise a plurality of alignmentapertures 6262 which can be configured to closely receive the staplelegs 6221 of the staples 6220. In at least one such embodiment, eachstaple 6220 can comprise a base 6222 and two staple legs 6221 extendingfrom the base 6222 wherein the bases 6222 of the staples 6220 can extendaround a bottom surface 6264 of the retention matrix 6260 and the staplelegs 6221 can extend upwardly through the alignment apertures 6262. Incertain embodiments, each alignment aperture 6262 can be circular, or atleast substantially circular, and can be defined by a diameter which isequal to or slightly larger than the diameter of the staple leg 6221extending therethrough. In various embodiments, the alignment matrix6260 can further comprise a plurality of raised members 6263 which canextend upwardly from the top surface 6261 of the alignment matrix 6260and surround, or at least partially surround, the alignment apertures6262. In certain embodiments, the raised members 6263 can provide forlonger alignment apertures 6262 wherein, in various circumstances,longer apertures 6262 can provide more control over the alignment of thestaple legs 6221 than shorter apertures 6262.

In use, in various embodiments, a first jaw supporting the staplecartridge 6200 can be positioned on one side of the tissue that is to bestapled and a second jaw supporting the retention matrix 6250 can bepositioned on the other side of the tissue. Once the jaws have beensuitably positioned relative to the tissue, in certain embodiments, thesecond jaw and the retention matrix 6250 can be moved toward the staplecartridge 6200. As the staple legs 6221 are being inserted through theretention apertures 6252 of the retention matrix 6250, in variousembodiments, a tissue-contacting, or bottom, surface 6251 of theretention matrix 6250 can contact the tissue and press the tissueagainst the tissue-contacting, or top, surface 6261 of the alignmentmatrix 6260. In various other embodiments, as described in greaterdetail further below, the staple cartridge 6200 can further comprise acompressible cartridge body positioned above the top surface 6261 of thealignment matrix 6260, for example, which can contact the tissue. Incertain embodiments, referring again to FIGS. 114 and 118, the alignmentmatrix 6260 can further comprise one or more apertures 6203 definedtherein which, when the alignment matrix 6260 is positioned againsttissue, can be configured to receive a portion of the tissue therein. Inembodiments where a compressible cartridge body is positioned aboveand/or against the alignment matrix 6260, a portion of the compressiblecartridge body can enter into the apertures 6203 when the cartridge bodyis compressed. Similarly, the retention matrix 6250 can comprise aplurality of apertures 6202 which can be configured to receive at leasta portion of the tissue therein when the retention matrix 6250 ispositioned against the tissue.

As the staple legs 6221 of the staples 6220 are inserted through theretention apertures 6252 of the retention matrix 6250, further to theabove, the tips of the staple legs 6221 may protrude upwardly from thetop surface 6257 of the retention matrix 6250. In various circumstances,as described above, the tips of the staple legs 6221 may remain unbentafter they have been inserted through the retention apertures 6252. Incertain embodiments, referring now to FIGS. 121-124, a fastening systemcomprising the staple cartridge 6200 and the retention matrix 6250 mayfurther comprise a plurality of protective caps or covers, such as caps6270, for example, which can be assembled to the staple legs 6221protruding above the retention matrix 6250. In various embodiments, eachcap 6270 can entirely, or at least partially, cover the sharp end of astaple leg 6221 such that the sharp end does not contact tissuepositioned adjacent thereto. In at least one embodiment, referring nowto FIG. 124, each cap 6270 can comprise an aperture 6271 defined thereinwhich can be configured to closely receive a tip of a staple leg 6221therein. In various embodiments, the caps 6270 can be comprised of anelastomeric material, such as silicone, polyisoprene, sanoprene, and/ornatural rubber, for example. In at least one embodiment, the aperture6271 can comprise a perimeter or diameter which is smaller than theperimeter or diameter of the staple leg 6221 inserted therein. In atleast one such embodiment, the aperture 6271 in the protective cap 6270can expand in order to receive the staple leg 6221 therein. In variousalternative embodiments, the caps 6270 may not comprise apertures andthe tips of the staple legs 6221 can be configured to incise the caps6270 as the legs 6221 are inserted therein. In any event, in variousembodiments, each cap 6270 can be seated onto a staple leg 6221 untilthe base 6272 of the cap 6270 abuts, or is positioned adjacent to, thetop surface 6257 of the retention matrix 6250. In various circumstances,the caps 6270 can be configured such that they are seated snugly ontothe tips of the staple legs 6221 such that they are not easily removedtherefrom. In certain embodiments, each cap 6270 can comprise a conical,or at least substantially conical, outer surface, for example. Invarious embodiments, the caps 6270 can comprise any suitable shape, suchas shapes comprising a parabolic, or at least substantially parabolic,outer surface, for example.

In various embodiments, the fastener system described above, forexample, could be deployed using the surgical stapler depicted in FIGS.125-127, for example. In various embodiments, the end effector cancomprise a first jaw, or staple cartridge channel, 6230 which can beconfigured to support the staple cartridge 6200 therein and a second jaw6240 which can be configured to support the retention matrix 6250 andthe plurality of protective caps 6270. Referring primarily to FIG. 125,which illustrates the second jaw 6240 in an open configuration, the jaws6230 and 6240 can be positioned relative to tissue T such that thetissue T is positioned intermediate the retention matrix 6250 and thestaple cartridge 6200. In various embodiments, as discussed above, thestaple cartridge 6200 can further comprise a compressible cartridgebody, such as cartridge body 6210, for example, in which the staples6220 and the alignment matrix 6260 can be positioned. In at least onesuch embodiment, the tissue T can be positioned against a top surface ofthe cartridge body 6210. In certain embodiments, the second jaw 6240 cancomprise a plurality of recesses, or apertures, 6245 configured toreceive the plurality of protective caps 6270 and, in addition, one ormore retention features, or retainers, which can be configured to holdthe retention matrix 6250 in position over the caps 6270. In at leastone such embodiment, the retention matrix 6250 can be configured toretain the caps 6270 in the apertures 6245. In various embodiments,referring now to FIG. 137, each aperture 6245 can be configured toreceive a portion of, or the entirety of, a cap 6270 therein. In certainembodiments, the apertures 6245 can be sufficiently sized and configuredsuch that the caps 6270 can be secured therein by at least one of apress-fit and/or snap fit arrangement, for example. In some embodiments,at least one adhesive could be utilized to secure the caps 6270 in theapertures 6245. In at least one such embodiment, such an adhesive couldbe selected such that caps 6270 can detach from the second jaw 6240after the caps 6270 have been engaged with the staple legs 6221 and thesecond jaw 6240 is moved away from the implanted fastener assembly. Incertain embodiments, referring now to FIG. 138, the second jaw 6240 canfurther comprise at least one cover sheet 6246 which can be assembled tothe second jaw 6240 and can extend over and retain the caps 6270 in theapertures 6245. In at least one such embodiment, at least a portion ofthe cover sheet 6246 can be secured to the jaw 6240 utilizing at leastone adhesive, for example. In use, in at least one embodiment, the coversheet 6246 can be at least partially detached from the jaw 6240 beforethe end effector is inserted into a surgical site. In certainembodiments, the cover sheet 6246 can be comprised of an implantablematerial, such as PDS and/or PGA, for example, which can be incised bythe staple legs 6221 as the staple legs 6221 emerge from the retentionmatrix 6250. In at least one such embodiment, the cover sheet 6246 canbe secured in the fastening system intermediate the covers 6270 and theretention matrix 6250.

Further to the above, referring now to FIG. 126, the jaw 6240 can bemoved from an open position to a closed position in which the tissue Tis positioned against the retention matrix 6250 and the cartridge body6210. In such a position, the retention matrix 6250 may not yet beengaged with the staples 6220. In various embodiments, the jaw 6240 canbe moved between its open position and its closed position by anactuator 6235. In at least one such embodiment, the jaw 6240 cancomprise a distal pin 6243 and a proximal pin 6244 extending therefrom,wherein the distal pin 6243 can slide vertically, or at leastsubstantially vertically, within a distal slot 6233 defined in thecartridge channel 6230, and wherein the proximal pin 6244 can slidevertically, or at least substantially vertically, within a proximal slot6234 which is also defined in the staple cartridge channel 6230. In use,the actuator 6235 can be retracted proximally in order to drive the pins6243 and 6244 into the upper ends of their respective slots 6233 and6234 as illustrated in FIG. 126. In at least one such embodiment, theactuator 6235 can comprise a distal drive slot 6236 and a proximal driveslot 6237, wherein the sidewalls of the drive slots 6236 and 6237 can beconfigured to contact the distal pin 6243 and the proximal pin 6244,respectively, and drive the pins 6243 and 6244 upwardly as the actuator6235 is moved proximally. More particularly, as the actuator 6235 ismoved proximally, the distal pin 6243 can slide up an inclined firstportion 6236 a of the distal drive slot 6236 into an intermediate, orsecond, portion 6236 b and, similarly, the proximal pin 6244 can slideup an inclined first portion 6237 a of the distal drive slot 6237 intoan intermediate, or second, portion 6237 b. As the pins 6243 and 6244are both moved upwardly, the jaw 6240 can be rotated downwardly towardthe tissue T into a closed position.

Further to the above, referring now to FIG. 127, the actuator 6235 canbe pulled further proximally in order to push the second jaw 6240downwardly toward the first jaw 6230, compress the cartridge body 6210,and engage the retention matrix 6250 and the plurality of protectivecaps 6270 with the staple legs of the staples 6220. In at least one suchembodiment, the additional proximal movement of the actuator 6235 cancause the sidewalls of the drive slots 6236 and 6237 to contact the pins6243 and 6244, respectively, and drive the pins 6243 and 6244 downwardlytoward the bottom ends of the slots 6233 and 6234, respectively. In suchcircumstances, the actuator 6235 can be pulled proximally such that,one, the distal pin 6243 exits the second portion 6236 b of the driveslot 6236 and enters into an inclined third portion 6236 c and,similarly, the proximal pin 6244 exits the second portion 6237 b of thedrive slot 6237 and enters into an inclined third portion 6237 c. As thepins 6243 and 6244 are both moved downwardly, the second jaw 6240 canmove downwardly toward the first jaw 6230 into a fired position. In atleast one such embodiment, the second jaw 6240 can be moved downwardlysuch that the retention matrix 6250 remains parallel, or at leastsubstantially parallel, to the top surface of the cartridge body 6210and/or parallel, or at least substantially parallel, to the alignmentmatrix 6260. In any event, once the retention matrix 6250 and theprotective caps 6270 have been engaged with the staple legs 6221 of thestaples 6220, as illustrated in FIG. 129, the second jaw 6240 can bereturned to an open, or an at least substantially open, position. In atleast one such embodiment, the actuator 6235 can be pushed distally inorder to drive the pins 6243 and 6244 to the top ends of the slots 6233and 6234, respectively, and then driven downwardly toward the bottomends of the slots 6233 and 6234 once the pins have passed through theintermediate portions 6236 b and 6237 b of the respective drive slots6236 and 6237. Once the second jaw 6240 has been opened, the first jaw6230 can be detached from the implanted staple cartridge 6200 and thefirst and second jaws 6230, 6240 can be removed away from the implantedfastener assembly, as illustrated in FIG. 128.

Referring to FIG. 127 once again, the reader will note that the pins6243 and 6244 are not illustrated as being seated in the very bottoms oftheir respective slots 6233 and 6234 eventhough the retention matrix6250 and the caps 6270 have been engaged with the staple legs 6221. Suchcircumstances can arise when thick tissue T is positioned between theretention matrix 6250 and the cartridge body 6210. In circumstanceswhere thinner tissue T is positioned between the retention matrix 6250and the cartridge body 6210, referring now to FIG. 130, the pins 6243and 6244 can be drive further downwardly into their respective slots6233 and 6234 as illustrated in FIG. 132. In general, in at least onesuch embodiment, the actuator 6235 can be pulled proximally in order todrive the pins 6243 and 6244 upwardly and downwardly through theprogressions described above and illustrated in FIGS. 130-132 and, owingto the thinner tissue T, the retention matrix 6250 and the protectivecaps 6270 can be driven further onto the staple legs 6221 of the staples6220, as illustrated in FIGS. 133 and 134. In various embodiments, as aresult of the adjustability afforded by the retention matrix 6250, thesame, or at least substantially the same, compressive pressure can beobtained in the fastened tissue regardless of whether the tissuecaptured within the end effector is thick or thin. In certainembodiments, the adjustability afforded by the retention matrix 6250 canallow a surgeon can select whether to apply a larger compressivepressure or a smaller compressive pressure to the tissue by selectingthe depth to which the retention matrix 6250 is seated. In at least onesuch embodiment, the range in which the retention matrix 6250 can beseated onto the staple legs 6221 can be determined by the lengths, orranges, of the slots 6233 and 6234, for example.

In various embodiments, as described above, the protective caps 6270 canbe comprised of a soft or flexible material, for example, which can beconfigured to grip the ends of the staple legs 6221. In certainembodiments, the protective caps 6270 can be comprised of abioabsorbable plastic, polyglycolic acid (PGA) which is marketed underthe trade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone(PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which ismarketed under the trade name Monocryl, polycaprolactone (PCL), and/or acomposite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example, and/or abiocompatible metal, such as titanium and/or stainless steel, forexample. As illustrated in FIG. 124, in at least one embodiment, eachcap 6270 can be unconnected to the other caps 6270. In certain otherembodiments, one or more caps 6270 can be mounted to the retentionmatrix 6250. In at least one such embodiment, the caps 6270 can beconnected to the retention matrix 6250 by at least one adhesive, forexample, wherein the apertures 6271 in the caps 6270 can be aligned, orat least substantially aligned, with the retention apertures 6252 in theretention matrix 6270. In various embodiments, referring now to FIG.135, a protective cap, such as a cap 6370, for example, can define aninner cavity, or dome, 6374 which can be configured to receive a tip ofa staple leg 6221, for example, therein. In at least one suchembodiment, the cap 6370 can comprise a bottom 6372 and an aperture 6371extending through the bottom 6372. In various embodiments, the aperture6371 can be defined by one or more deflectable members 6373 which can beconfigured to deflect when the staple leg 6221 is inserted therethrough.In certain embodiments, two or more caps 6370, for example, can beconnected together to form an array of caps 6370. In at least one suchembodiment, referring now to FIG. 136, a plurality of caps 6370 can beconnected together by a sheet of material 6375. In certain embodiments,the sheet 6375 can be sufficiently rigid in order to maintain a desiredarrangement and/or alignment of the caps 6370. In at least oneembodiment, the caps 6370 can be comprised of a biocompatible metal,such as titanium and/or stainless steel, for example, and the sheet 6375can be comprised of a bioabsorbable plastic, polyglycolic acid (PGA)which is marketed under the trade name Vicryl, polylactic acid (PLA orPLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone25 (PGCL) which is marketed under the trade name Monocryl,polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCLand/or PCL, for example. In various embodiments, a sheet 6375 can becomprised of a bioabsorbable material including an anti-microbial agent,such as colloidal silver and/or triclosan, for example, stored and/ordispersed therein which can be released as the sheet 6375 isbioabsorbed, for example.

In various embodiments, further to the above, the sheet 6375 can beinjection molded around the caps 6370 utilizing an injection moldingprocess, for example, such that the caps 6370 are embedded in the sheet6375. In certain other embodiments, the sheet 6375 can be moldedutilizing an injection molding process, for example, wherein apertures6376 can be formed in the sheet 6375 during the injection moldingprocess and/or after the injection molding process utilizing a stampingprocess, for example. In either event, the caps 6370 can be insertedinto and secured in the apertures 6376 utilizing a press-fit and/orsnap-fit interconnection and/or at least one adhesive. In certainembodiments, each cap 6370 can comprise an annular groove surrounding,or at least partially surrounding, the perimeter of the cap 6370 whichcan be configured to receive the perimeter of an aperture 6376 therein.In certain embodiments, the sheet 6375 can be comprised of a flexibleand/or pliable material which can permit relative movement between thecaps 6370. In at least one such embodiment, the flexible sheet 6375 canbe comprised of a rubber, plastic, and/or silicone material, forexample, and the caps 6370 can be comprised of a rigid material, such asmetal, for example. In at least one such embodiment, similar to theabove, the flexible material can be molded around the caps 6370. Incertain embodiments, the caps 6370 can be pressed into a pre-moldedsheet 6375, for example. In various embodiments, the durometer of theflexible material can be selected to provide a desired stiffness of thesheet 6375. In certain embodiments, the sheet 6375 can be configuredsuch that it comprises a flexible band. In any event, the sheet 6375 canfacilitate the assembly of the caps 6370 into an end effector as aplurality of the caps 6370 can be positioned and/or alignedsimultaneously within the end effector. Furthermore, the sheet 6375connecting the caps 6370, once implanted, can strengthen or bolster thetissue along the staple line, for example. In addition to or in lieu ofa sheet connecting the caps 6370, the caps 6370 can be connectedtogether by a plurality of links. In at least one such embodiment, suchlinks can be flexible and can permit relative movement between the caps6370.

In various embodiments, referring now to FIGS. 139 and 140, a protectivecap, such as cap 6470, for example, can comprise a forming surface whichcan be configured to deform a tip of a staple leg. In at least one suchembodiment, the cap 6470 can comprise a base 6472 which can include anaperture 6471 extending therethrough. In various embodiments, theaperture 6471 can be configured to closely receive a staple leg, such asa staple leg 6221, for example, therein. In at least one embodiment, theaperture 6471 can be defined by a diameter or perimeter which can beequal to or larger than the diameter or perimeter of the staple leg6221. In various embodiments, the cap 6470 can further comprise acavity, or dome, 6474 which can be configured to receive the tip of thestaple leg 6221 as it is inserted into the cap 6470. Referring primarilyto FIG. 140, the cap 6470 can further comprise an anvil, or formingsurface, 6473 which can be configured to deflect and deform the stapleleg 6221. In various circumstances, the forming surface 6473 can becurved and/or concave, for example, and can be configured to curl thestaple leg 6221 as it is inserted into the cap 6470. In certainembodiments, the staple leg 6221 can be sufficiently deformed such thatit cannot be withdrawn through the aperture 6471 and, as a result, thecap 6470 can become locked to the staple leg 6221. In at least one suchembodiment, the base 6472 of the cap 6470 can define a lip extendingaround the aperture 6471 which can prevent the deformed staple leg 6221from being removed from the cavity 6474. In various circumstances, as aresult of the above, one or more caps 6470 can prevent, or inhibit, aretention matrix, such as retention matrix 6250, for example, frombacking up or being disengaged from the staples 6220. In variousembodiments, although not illustrated, the cap 6470 can besymmetrically, or at least substantially symmetrically, formed, and theaperture 6471 can be located along a central axis 6479 extending throughthe cap 6470. In various alternative embodiments, referring again toFIG. 139, the aperture 6471 can be offset with respect to the centralaxis 6479. In at least one such embodiment, the offset aperture 6471 canallow the staple leg 6221 to contact a side of the forming surface 6473and curl over to the other side of the forming surface 6473 instead ofcontacting the center of the forming surface 6473, as may occur inembodiments comprising a centered aperture 6471 mentioned above.

In various embodiments, as discussed above, a retention matrix, such asretention matrix 6250, for example, can be comprised of a sheet ofmaterial and a plurality of retention apertures 6252 extendingtherethrough. In at least some embodiments, the sheet of materialcomprising the retention matrix 6250 can be rigid or substantiallyinflexible. In certain other embodiments, a retention matrix can becomprised of an array of retention matrix elements and a plurality offlexible connectors, or links, connecting the retention matrix elements.In various embodiments, referring now to FIG. 141, a retention matrix,or a portion of retention matrix, 6550 can comprise a plurality ofelement bodies 6505 which can be connected together by one or moreconnecting links 6507. In at least one embodiment, each element body6505 can comprise a plurality of deformable members 6553 which define aretention aperture 6552 therein. In certain embodiments, the elementbodies 6505 and the connecting links 6507 of a retention matrix 6550 canbe integrally formed and can comprise a unitary piece of material. Invarious embodiments, the retention matrix 6550 can be stamped or cast,for example, from a metal material, such as titanium and/or stainlesssteel, for example. In at least one embodiment, the retention matrix6550 can be comprised of plastic, such as polyetheretherketone (PEEK),polypropylene which is marketed under the trade name Prolene, polyester,polyethylene terephthalate which is marketed under the trade namesEthibond and Mersilene, polyvinylidene fluoride, polyvinylidenefluoride-co-hexafluoropropylene, poly hexafluoropropylene-VDF which ismarketed under the trade name Pronova, and/or long-chain aliphaticpolymers Nylon 6 and Nylon 6,6 which are marketed under the trade namesEthilon & Nurolon, for example, and can be formed by an injectionmolding process, for example. In certain embodiments, the element bodies6505 may not be integrally formed with the connecting links 6507. Invarious embodiments, a plurality of singular element bodies 6505 can beproduced which are subsequently connected together and embedded in aretention matrix. In at least one such embodiment, the element bodies6505 can be stamped from a metal material, such as titanium and/orstainless steel, for example, and placed in a plastic injection moldwherein a plastic material can be injected into the mold to form, one, arim 6506 of material surrounding, or at least partially surrounding, theelement bodies 6505 and, two, connecting links 6507 extending from therims 6506. In certain other embodiments, one or more connector latticescan be formed comprising apertures defined within a plurality of rims6506 wherein each such aperture can be configured to receive an elementbody 6505 therein. In at least one embodiment, each element body 6505can comprise a circular, or at least substantially circular, outerperimeter and, similarly, each rim 6506 can define a circular, or atleast substantially circular, aperture therein, wherein the diameter ofthe aperture can be equal to or smaller than the diameter of the elementbody 6505. In at least one such embodiment, the element bodies 6505 canbe press-fit or embedded into the apertures in the rims 6505. In certainembodiments, the element bodies 6505 can be secured in the aperturesutilizing at least one adhesive.

In various embodiments, further to the above, a retention matrix cancomprise a plurality of element bodies 6505 and a plurality ofconnecting links 6507 which can connect the element bodies 6505 in anysuitable array, such as those illustrated in FIGS. 142-145, for example.Regardless of the pattern of the array, in various embodiments, theconnecting links 6507 can be configured to allow the element bodies 6505and the retention apertures 6552 to move relative to one another. In atleast one such embodiment, the lattice of element bodies 6505 andconnecting links 6507 comprising the retention matrix 6550, once engagedwith tissue, can be configured to stretch, twist, contract, and/orotherwise flex in order to permit at least some movement within thetissue yet, at the same time, resist larger movements thereof. Invarious embodiments, each connecting link 6507 can comprise a flexiblemember configured to stretch, twist, and/or contract in order to permitthe retention matrix 6550 to flex intermediate the matrix retentionelements 6505, for example. Referring again to FIG. 141, each link 6507extending from a rim 6506 can be defined by a width which is narrowerthan the width of the element body 6505 and/or the rim 6506. In certainembodiments, referring to FIGS. 142-145, one or more links 6507 cancomprise straight portions which extend along a line between adjacentelement bodies 6506, for example. In at least one such embodiment, eachlink 6507 can comprise a first end attached to a first rim 6506 and asecond end attached to a second rim 6506. In certain embodiments,referring once again to FIG. 141, two or more links 6507 can beconnected to one another. In at least one such embodiment, two or morelinks 6507 can be connected at an intermediate hinge 6509, for example.In various embodiments, the hinge 6509 can comprise a reduction incross-sectional thickness in one or more directions as compared to thecross-sectional thickness of the links 6507 which can permit theconnected links 6507 to move relative to each other, for example. Incertain embodiments, the retention matrix 6550 can further comprisehinges 6508 which can connect the links 6507 to the rims 6506 and permitrelative movement between the links 6507 and the rims 6506. Similar tohinges 6509, hinges 6508 can comprise a reduction in cross-sectionalthickness in one or more directions as compared to the cross-sectionalthickness of the links 6507, for example.

In various embodiments, further to the above, the connected links 6507can extend in different directions. In at least one such embodiment, afirst link 6507 can extend in a first direction and a second link 6507can extend in a second direction, wherein the first direction can bedifferent than the second direction. In certain embodiments, the firstlink 6507 can extend along a first line and the second link 6507 canextend along a second line, wherein the first line and the second linecan intersect each other at an angle, such as approximately 30 degrees,approximately 45 degrees, approximately 60 degrees, and/or approximately90 degrees, for example. In various embodiments, the hinges 6508 and/orhinges 6509 can comprise living hinges which can permit the links 6507to move relative to each other a number of times without breaking. Incertain embodiments, the hinges 6508 and/or hinges 6509 can comprisefrangible, or easily-breakable, portions which can break when flexed toofar and/or flexed too many times. In at least one such embodiment, suchfrangible portions can permit one or more portions of the retentionmatrix 6550 to break away from another portion of the retention matrix6550. In various embodiments, the hinges 6508 and/or hinges 6509, forexample, can comprise sections of the retention matrix 6550 which areeasier to incise than the other portions of the retention matrix 6550.More particularly, an implanted retention matrix, and the tissuefastened by the implanted retention matrix, may oftentimes by incised bya cutting member for various reasons and, in order to facilitate suchcross-cutting, the hinges 6508 and/or hinges 6509 can provide avenues,or thin sections, through which a cutting member can more easily passthrough the retention matrix 6550, for example. In various embodiments,further to the above, the connecting links 6507 can comprise one or morecoined features or material upsets, for example, defined therein whichcan facilitate the bending, breakage, and/or incision of the connectinglinks 6507.

In various embodiments, a retention matrix can comprise a plurality ofretention matrix elements, such as matrix element bodies 6505, forexample, which can be embedded in a flexible sheet, or band, ofmaterial. In at least one embodiment, a flexible sheet of material canbe formed from a bioabsorbable, elastomeric material, such as silicone,for example, wherein the flexible sheet can be produced with a pluralityof apertures defined therein. In at least one such embodiment, a solidflexible sheet can be molded and a plurality of apertures can be punchedout of the flexible sheet. In various alternative embodiments, theflexible sheet can be molded and the apertures defined therein can beformed during the molding process. In either event, the retention matrixelements 6505, for example, can be inserted into and retained within theflexible sheet. In certain other embodiments, similar to the above, theflexible sheet can be formed around the matrix elements 6505. In atleast one embodiment, the flexible sheet can be comprised of a wovenmesh, for example, and/or any other suitable material. Such a wovenmesh, further to the above, may be easy to cross-cut.

In various embodiments, referring now to FIGS. 146 and 147, a fastenersystem comprising a retention matrix, such as retention matrix 6250, forexample, can further comprise a cover, such as cover 6670, for example,which can cover the tips of the staple legs 6221 when they extend abovethe top surface 6257 of the retention matrix 6250. In variousembodiments, the cover 6670 can be attached to the retention matrix6250. In certain embodiments, the cover 6670 and/or the retention matrix6250 can comprise retention features which can be configured to retainthe cover 6670 to the retention matrix 6250. In at least one embodiment,at least one adhesive can be utilized to adhere the cover 6670 to theretention matrix 6250. In at least one embodiment, the cover 6670 can becomprised of a single layer, although the cover 6670 is illustrated ascomprising two layers as described in greater detail further below. Invarious embodiments, referring primarily to FIG. 147, the tips of thestaple legs 6221 can extend through a bottom surface 6673 of the cover6670; however, the cover 6670 can comprise a sufficient thickness suchthat the staple tips do not extend through the top surface 6675 of thecover 6670. In at least one such embodiment, as a result, the tips ofthe staple legs 6221 may not protrude from the cover 6670. In variousembodiments, the cover 6670 can comprise a plurality of layers. In atleast one such embodiment, the cover 6670 can comprise a first layer6671 and a second layer 6672. In at least one embodiment, the firstlayer 6671 and the second layer 6672 can be attached to one anotherwherein, in at least one embodiment, the second layer 6672 can comprisea bottom surface 6676 which is adhered to the first layer 6671. Invarious embodiments, the first layer 6671 and the second layer 6672 cancomprise different thicknesses while, in certain embodiments, they cancomprise the same thickness. In at least one embodiment, the first layer6671 and the second layer 6672 can comprise substantially the same widthand/or length. In alternative embodiments, the layers 6671 and 6672 cancomprise different widths and/or lengths.

In various embodiments, further to the above, the first layer 6671 canbe comprised of a compressible foam, mesh material, and/or hydrogel, forexample, which can be incised by the staple legs 6211. In at least oneembodiment, the second layer 6672 can be comprise of a tougher material,or skin, such as PGA and/or PDS, for example, and/or any suitablebuttress material. In at least one such embodiment, the staple legs 6221can be configured to penetrate the first layer 6671; however, in variousembodiments, the staple legs 6221 may be unable to penetrate the secondlayer 6672. In certain embodiments, the second layer 6672 can becomprised of a material having a sufficient resiliency and/or toughnesswhich can permit the second layer 6672 to be contacted and displaced bythe staple leg 6221 but not be incised, or only marginally incised, bythe staple tip of the staple leg 6221. Although not illustrated, a covercan comprise more than two layers wherein one or more of such layers maybe penetration-resistant. In use, in at least one such embodiment, theretention matrix 6250 can be positioned against the tissue to befastened and pushed downwardly such that the staple legs 6221 of thestaples 6220 are pushed through the tissue T and the retention apertures6252 in the retention matrix 6250 and enter into the first layer 6271 ofthe cover 6270. In various embodiments, the tips of the staple legs 6221may not enter, or at least substantially enter, into the second layer6272 of the cover 6270. After the retention matrix 6250 has beensuitably positioned, the jaw 6240 can be opened and the cover 6670 andthe retention matrix 6250 can detach from the jaw 6240 as illustrated inFIG. 146. As illustrated in FIG. 146, a jaw 6640 can be configured tohold more than one retention matrix 6250 and cover 6670. In at least onesuch embodiment, the jaw 6640 can comprise two channels 6679 which eachcan be configured to receive a cover 6670 therein and a retention matrix6250 positioned thereover such that the tissue-contacting surface 6251of each retention matrix 6250 depends downwardly from the bottom of thejaw 6240. In at least one such embodiment, a retention matrix 6250 and acover 6270 can be housed in the jaw 6640 on each side of a knife slot6678. In use, both retention matrices 6250 and covers 6670 can bedeployed simultaneously and/or to the same depth with respect toopposing staple cartridges, such as cartridges 6200, for example,positioned thereacross. Thereafter, in various embodiments, the fastenedtissue can be incised along a cutting line by a cutting member thattraverses the knife slot 6678 wherein the jaw 6640 can then bere-opened. In certain embodiments, the covers 6670 may not be attachedto the retention matrix 6250. In at least one such embodiment, thecovers 6670 can be positioned in the channels 6679 and can be retainedin the channels 6679 by the retention matrices 6250 which can be securedto the jaw 6640. In various embodiments, the each retention matrix 6250can be wider and/or longer than their respective covers 6670 such thatthe retention matrices 6250 can retain the entirety of their covers 6670in position. In certain embodiments, each retention matrix 6250 cancomprise the same width and/or length as their respective cover 6670,for example.

In various embodiments, as described above, a fastener system cancomprise a layer of material which can be attached to a retentionmatrix, such as retention matrix 6250, for example. In at least oneembodiment, referring now to FIG. 150, a layer of material 6870 can beattached to the bottom surface 6251 of the retention matrix 6250. Incertain embodiments, the layer 6870 and/or the retention matrix 6250 cancomprise retention features which can be configured to retain the layer6870 to the retention matrix 6250. In at least one embodiment, at leastone adhesive can be utilized to adhere the layer 6870 to the retentionmatrix 6250. In any event, the layer 6870 can comprise a bottom, ortissue-contacting, surface 6873 which can be configured to contact thetissue T when the retention matrix 6250 is moved downwardly toward thestaples 6220 to engage the retention apertures 6252 with the staple legs6221. In at least one such embodiment, the layer 6870 can be comprisedof a compressible material, such as a bioabsorbable foam, for example,which can be compressed between the bottom surface 6251 of the retentionmatrix 6250 and the tissue T. In various embodiments, the layer 6870 canfurther comprise at least one medicament stored and/or absorbed thereinwhich can be expressed from the layer 6870 as the layer 6870 iscompressed. In at least one embodiment, the medicament can comprise atleast one tissue sealant, hemostatic agent, and/or anti-microbialmaterial, such as ionized silver and/or triclosan, for example. Invarious embodiments, the compression of the layer 6870 can squeeze themedicament from the layer 6870 such that the entirety of, or at least asignificant portion of, the surface of the tissue T is covered with themedicament. Furthermore, as the layer 6870 is compressed and the staplelegs 6221 penetrate the tissue T and the layer 6870, the medicament canflow down the staple legs 6221 and treat the tissue that has just beenincised by the staple legs 6221, for example. In various embodiments,the body of the retention matrix 6250 can comprise a first layer whichis comprised of a biocompatible material, such as titanium and/orstainless steel, for example, and the bottom layer 6870 can comprise asecond layer comprised of a bioabsorbable material, such as oxidizedregenerated cellulose (ORC), biologically active agents like fibrinand/or thrombin (either in their liquid state or freeze dried),glycerin, absorbable porcine gelatin in either flue or foamconfigurations, and/or anti-microbials, such as ionized silver and/ortriclosan, for example. Additional bioabsorbable materials can compriseSurgicel Nu-Knit, Surgicel Fibrillar, collagen/ORC which is a hybridwith a built in collagen matrix and is marketed under the trade namePromogran, polyglycolic acid (PGA) which is marketed under the tradename Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS),polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketedunder the trade name Monocryl, polycaprolactone (PCL), and/or acomposite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. Althoughonly one layer 6870 is illustrated in FIG. 150, any suitable number oflayers could be used. In at least one embodiment, a first layercomprising a first medicament could be attached to the retention matrix6250 and a second layer comprising a second, or different, medicamentcould be attached to the first layer. In at least one such embodiment, aplurality of layers could be used wherein each layer can comprise adifferent medicament and/or a different combination of medicamentscontained therein.

In various embodiments, referring now to FIG. 148, a fastener system cancomprise a layer of material 6770 attached to the bottom surface 6251 ofthe retention matrix 6250. In certain embodiments, the layer 6770 and/orthe retention matrix 6250 can comprise retention features which can beconfigured to retain the layer 6770 to the retention matrix 6250. In atleast one embodiment, at least one adhesive can be utilized to adherethe layer 6770 to the retention matrix 6250. In any event, the layer6770 can comprise a bottom, or tissue-contacting, surface 6773 which canbe configured to contact the tissue T when the retention matrix 6250 ismoved downwardly toward the staples 6220 to engage the retentionapertures 6252 with the staple legs 6221. In at least one suchembodiment, the layer 6770 can be comprised of a compressible material,such as a bioabsorbable foam, for example, which can be compressedbetween the surface 6251 of the retention matrix 6250 and the tissue T.In various embodiments, the layer 6770 can further comprise one or moreencapsulations, or cells, 6774 which can be configured to store at leastone medicament therein. In certain embodiments, referring to FIG. 149,the encapsulations 6774 can be aligned, or at least substantiallyaligned, with the retention apertures 6252 such that, when the staplelegs 6221 are pushed through the tissue T and the layer 6770, the staplelegs 6221 can puncture and/or otherwise rupture the encapsulations 6774.After the encapsulations 6774 have been ruptured, the at least onemedicament M stored in the encapsulations 6774 can flow out onto thetissue T. In at least one such embodiment, the medicament M can comprisea fluid which can flow or wick down the staple legs 6221 and treat thetissue T that was just incised by the staple legs. As a result of theabove, the medicament stored within the encapsulations 6774 can providea localized treatment to the tissue. In certain embodiments, theencapsulations 6774 in the sheet 6770 can comprise different medicamentsstored therein. For example, a first group of encapsulations 6774 cancomprise a first medicament, or a first combination of medicaments,stored therein and a second group of encapsulations can comprise adifferent medicament, or a different combination of medicaments, storedtherein. In various embodiments, the layer 6770 can be comprised of aflexible silicone sheet and the encapsulations 6774 can represent voidsin the silicone sheet. In at least one such embodiment, the siliconesheet can comprise two layers that can be attached to one anotherwherein the encapsulations 6774 can be defined between the two layers.In various embodiments, the layer 6770 can comprise one or more thinsections or weakened portions, such as partial perforations, forexample, which can facilitate the incision of the layer 6770 and therupture of the encapsulations 6774 by the legs 6221. In certainembodiments, at least a portion of the encapsulations 6774 can bepositioned within domes 6777, wherein the domes 6777 can extend upwardlyfrom the sheet 6770. In at least one such embodiment, the domes 6777and/or at least a portion of the encapsulations 6774 can be positionedwithin the pockets 6201 formed within the retention matrix 6250. Incertain embodiments, the encapsulations 6774 may comprise discrete cellswhich are unconnected to each other. In certain other embodiments, oneor more of the encapsulations 6774 can be in fluid communication witheach other via one or more passageways, conduits, and/or channels, forexample, extending through the layer 6770. The disclosure of U.S. Pat.No. 7,780,685, entitled ADHESIVE AND MECHANICAL FASTENER, which issuedon Aug. 24, 2010, is hereby incorporated by reference in its entirety.

In various embodiments, further to the above, a staple cartridgecomprising a cartridge body, staples, and/or an alignment matrix thereincan be loaded into a first jaw of an end effector and, similarly, aretention matrix and/or one or more covers can be loaded into a secondjaw of the end effector. In certain embodiments, referring now to FIG.151, an instrument, such as cartridge loader 6990, for example, can beused to insert two or more fastener cartridges into an end effector atthe same. In at least one embodiment, the cartridge loader 6990 cancomprise a handle 6991 and a cartridge carrier 6992, wherein thecartridge carrier 6992 can comprise a first retention portion configuredto retain the cartridge body 6210 of the staple cartridge 6200 theretoand, in addition, a second retention portion configured to retain acartridge body 6980 which supports, one, a plurality of protective caps6270 therein and, two, a retention matrix 6250 along the bottom surfacethereof, for example. In various embodiments, the first and secondretention portions can each comprise one or more retention membersconfigured to releasably engage the cartridge bodies 6210 and 6980. Inuse, referring now to FIGS. 152 and 153, an end effector can comprise afirst, or bottom, jaw 6230 and a second, or top, jaw 6940, wherein thestaple cartridge 6200 can be loaded into the first jaw 6230 and thecartridge body 6980 can be loaded into the second jaw 6940. In variouscircumstances, the top jaw 6940 can be rotated from an open position(FIG. 152) to a closed position (FIG. 153) by an actuator 6235, whereinthe operation of the actuator 6235 is described above and is notrepeated herein for the sake of brevity. Once the top jaw 6940 is in itsclosed position, referring now to FIG. 153, the distal end 6993 of thecartridge carrier 6992 can be inserted into the end effector such thatthe staple cartridge 6200 is slid through the distal end 6938 of thefirst jaw 6930 and into a first attachment portion, or channel, 6939 inthe first jaw 6230. Similarly, the distal end 6993 of the cartridgecarrier 6992 can be inserted into the end effector such that thecartridge body 6980 is slid through the distal end 6948 of the secondjaw 6940 and into a second attachment portion, or channel, 6949 in thesecond jaw 6940. A surgeon, or other clinician, holding the handle 6991of the cartridge loader 6990 can push the staple cartridge 6200 and thecartridge body 6980 through the channels 6939 and 6949, respectively,until the staple cartridge 6200 and the cartridge body 6980 are fullyseated therein.

As the staple cartridge 6200 and the cartridge body 6980 are beingseated, the staple cartridge 6200 and the cartridge body 6980 can eachengage one or more retention portions in their respective jaws 6230 and6940, as described in greater detail further below. In any event, oncethe staple cartridge 6200 and the cartridge body 6980 have been seated,referring now to FIG. 154, the cartridge loader 6990 can be detachedfrom the staple cartridge 6200 and the cartridge body 6980 and removedfrom the end effector. In at least one such embodiment, the retentionforce holding the staple cartridge 6200 in the first jaw 6230 can begreater than the retention force holding the staple cartridge 6200 tothe cartridge carrier 6992 such that, as the cartridge carrier 6992 ispulled distally out of the end effector, the staple cartridge 6200 canremain behind in the first jaw 6230. Similarly, the retention forceholding the cartridge body 6980 in the second jaw 6940 can be greaterthan the retention force holding the cartridge body 6940 to thecartridge carrier 6992 such that, as the cartridge carrier 6992 ispulled distally out of the end effector, the cartridge body 6940 canremain behind in the second jaw 6940. Once the cartridge loader 6990 hasbeen removed from the end effector, the loaded first jaw 6230 and theloaded second jaw 6940 can be positioned relative to the tissue T thatis to be stapled. Referring now to FIG. 155, the second jaw 6940 can bemoved from an open position (FIG. 154) to a fired position (FIG. 155) inorder to engage the retention matrix 6250 and the plurality ofprotective caps 6270 carried by the cartridge body 6980 with the staples6220 positioned within the staple cartridge 6200.

Referring now to FIGS. 156 and 157, the second jaw 6940 can be re-openedand the plurality of protective caps 6270 and the retention matrix 6250can detach from the cartridge body 6980 such that the caps 6270 and theretention matrix 6250 can remain engaged with the tissue T and thestaple cartridge 6200. In at least one embodiment, the cartridge body6980 can comprise a plurality of pockets in which the plurality of caps6270 can be removably positioned and one or more retention slotsconfigured to removably retain the retention matrix 6250 thereto. Invarious embodiments, the retention members of the second jaw 6940engaged with the cartridge body 6980 can retain the cartridge body 6980in the second jaw 6940 after the second jaw 6940 has been opened. Incertain embodiments, the cartridge body 6980 can be configured to tearas the second jaw 6940 is opened such that a portion of the cartridgebody 6980 is implanted with the caps 6270 and the retention matrix 6250and a portion of the cartridge body 6980 remains in the second jaw 6940.Similarly, referring again to FIGS. 156 and 157, the retention membersof the first jaw 6230 engaged with the cartridge body 6210 can retainthe cartridge body 6210 in the first jaw 6230 after the second jaw 6940has been opened. In certain embodiments, the cartridge body 6210 can beconfigured to tear as the first jaw 6230 is pulled away from theimplanted cartridge 6200 such that a portion of the cartridge body 6210is implanted with the staples 6220 and alignment matrix 6260 and aportion of the cartridge body 6210 remains in the first jaw 6230. Invarious embodiments, referring now to FIGS. 158-160, a staple cartridge,such as staple cartridge 6900, for example, can comprise one or morelongitudinal retention slots 6913 extending along the length of thecartridge body 6910 which, when the staple cartridge 6900 is insertedinto a jaw 6930, for example, can be configured to receive one or morelongitudinal retention rails 6916 extending from the jaw 6930 therein.In use, in at least one embodiment, an end of the retention slots 6913can be aligned with the distal ends of the retention rails 6916 beforethe staple cartridge 6900 is slid through the distal end 6938 of theretention channel 6939, for example.

In various embodiments, referring again to FIG. 160, the jaw 6940 cancomprise two retention channels 6949, wherein each retention channel6949 can be configured to receive a cartridge body 6980 comprising aplurality of caps 6270 and a retention matrix 6250 therein. In certainembodiments, each cartridge body 6980 can comprise one or morelongitudinal retention shoulders 6917 which can be configured to be slidalong one or more longitudinal retention rails 6918 of the second jaw6940 as the cartridge bodies 6980 are inserted into their respectiveretention channels 6949 in jaw 6940. In various embodiments, theretention rails 6918 and the retention shoulders 6917 can co-operate toretain the cartridge body 6980 in the second jaw 6940 as the cartridgebodies 6980 are detached from the caps 6270 and the retention matrix6250 stored therein. In various embodiments, referring now to FIG. 159,the second jaw 6940 can further comprise one or more distal bumps, orretention members, 6915 extending therefrom which can be configured toremovably lock the cartridge bodies 6980 in their respective retentionchannels. In at least one such embodiment, the second jaw 6940 cancomprise a distal bump 6915 configured and positioned relative to eachretention channel 6949 such that each cartridge body 6980 can flexaround the bumps 6915 as the cartridge bodies 6980 are being insertedinto the channels 6949 wherein, just as the cartridge bodies 6915 arebeing fully seated in the channels 6949, the distal ends of thecartridge bodies 6980 can clear and snap over the bumps 6915. In orderto remove the cartridge bodies 6980 after they have been expended, asdescribed above, the cartridge bodies 6980 can be pulled back over thebumps 6915 and removed from the retention channels 6949. Similar to theabove, the first jaw 6930 can comprise one or more distal retentionbumps 6914 extending therefrom which can be configured to be received inone or more retention grooves, or slots, 6912 (FIG. 158) in thecartridge body 6910 when the staple cartridge 6900 has been fullyseated.

In various embodiments, further to the above, a first fastener cartridgecomprising a plurality of first fasteners positioned therein can bepositioned in a first jaw of a surgical fastening device and a secondfastener cartridge comprising a plurality of second fasteners positionedtherein can be positioned in a second jaw of the surgical fasteningdevice. In use, the first jaw and/or the second jaw can be moved towardthe other in order to engage the first fasteners with the secondfasteners and secure tissue therebetween. In certain embodiments, thefirst fastener cartridge and the second fastener cartridge can beengaged with each other as the first fasteners are engaged with thesecond fasteners. In at least one embodiment, the body of the firstfastener cartridge can be comprised of a first compressible material andthe body of the second fastener cartridge can be comprised of a secondcompressible material, wherein the first body and/or the second body canbe compressed against the tissue being fastened. After the tissue hasbeen fastened, the first jaw can be moved away from the implanted firstfastener cartridge and the second jaw can be moved away from theimplanted second fastener cartridge. Thereafter, the first jaw can bereloaded with another first fastener cartridge, or the like, and thesecond jaw can be reloaded with another second fastener cartridge, orthe like, and the surgical fastening instrument can be reused. Whilestaples can be used in some embodiments, other embodiments areenvisioned comprising other types of fasteners, such as two-partfasteners which are locked together when they are engaged with oneanother, for example. In at least one such embodiment, the firstfastener cartridge can comprise a first storage portion for storing thefirst fastener portions and the second fastener cartridge can comprise asecond storage portion for storing the second fastener portions. Invarious embodiments, the fastening systems described herein can utilizefasteners comprising any suitable type of material and/or form. Incertain embodiments, the fasteners can comprise penetrating members.Such penetrating members could be comprised of a polymer, a composite,and/or a multi-layered substrate, for example. An example of amulti-layered substrate could be a wire or a sheet substrate with anelastomeric or polymeric coating. It could be a thin sheet formed suchthat penetrating members are oriented perpendicular, or at leastsubstantially perpendicular, to the connecting member. The penetratingmembers could comprise a rectangular profile, semi-circular profile,and/or any beam profile. In various embodiments, the fasteners describedherein can be manufactured utilizing any suitable process, such as awire extruding process, for example. Another possibility is the use ofmicrofabrication to create hollow penetrating members. These penetratingmembers could be fabricated from a process which is different than awire extruded process and could use a combination of materials.

As described above, the tips of staple legs protruding through aretention matrix can be covered by one or more caps and/or covers. Incertain embodiments, the tips of the staple legs can be deformed afterthey have been inserted through the retention matrix. In at least oneembodiment, a jaw holding the retention matrix can further compriseanvil pockets positioned above and/or aligned with the retentionapertures which can be configured to deform the staple legs as theyprotrude above the retention matrix. In various embodiments, the staplelegs of each staple can be curled inwardly toward each other and/ortoward the center of the staple, for example. In certain otherembodiments, one or more of the staple legs of a staple can be curledoutwardly away from the other staple legs and/or away from the center ofthe staple. In various embodiments, regardless of the direction in whichthe staple legs are curled, the tips of the staple legs can contact thebody of the retention matrix and may not re-enter the tissue that hasbeen fastened by the staples. In at least one embodiment, thedeformation of the staple legs after they have passed through theretention matrix can lock the retention matrix in position.

In various embodiments, referring now to FIGS. 161 and 162, a surgicalstapling instrument, such as surgical stapler 7000, for example, cancomprise a first jaw 7030 and a second jaw 7040, wherein the second jaw7040 can be moved toward and away from the first jaw 7030 by themovement of actuator 6235. The operation of actuator 6235 is describedabove and is not repeated herein for the sake of brevity. In variousembodiments, the first jaw 7030 can comprise a distal end 7031 and aproximal end 7032, wherein the first jaw 7030 can define a channelextending between the distal end 7031 and the proximal end 7032 which isconfigured to receive a staple cartridge. For the purposes ofillustration, the cartridge body of such a staple cartridge is notdepicted in FIG. 161, although such a staple cartridge can comprise acartridge body, staples 6220 positioned within the cartridge body, andstaple drivers 7012 positioned underneath the staples 6220. In certainembodiments, although not illustrated in FIG. 161 for the sake ofclarity, the second jaw 7040 can be configured to hold a retentionmatrix, such as retention matrix 6250, for example, over the staples6220 and/or move the retention matrix into engagement with the legs ofthe staples 6220 as described above. In at least one embodiment, thesurgical stapler 7000 can further comprise a sled 7010 positioned in thefirst jaw 7030 which can be slid from the distal end 7031 of the firstjaw 7030 toward the proximal end 7032, for example, and lift the stapledrivers 7012, and the staple 6220 supported thereon, toward theretention matrix and the second jaw 7040. In various other embodiments,the sled 7010 can be moved from the proximal end 7032 toward the distalend 7031 in order to deploy the staples 6020, for example. In at leastone embodiment, the sled 7010 can comprise one or more inclined ramps,or cams, 7011 which can be configured to slide underneath the stapledrivers 7012 and lift the staple drivers 7012 upwardly. In variousembodiments, the surgical stapler 7000 can further comprise a pull, orpush, rod operably coupled to the sled 7010 which can be movedproximally and/or distally by an actuator located on a handle and/orshaft of the surgical stapler 7000, for example.

In various embodiments, referring again to FIG. 161, the second jaw 7040of the surgical stapler 7000 can comprise a frame 7041, a distal end7048, and a proximal end 7049 positioned opposite the distal end 7048.In certain embodiments, the second jaw 7040 can further comprise a guidesystem comprising one or more guide rails, such as guide rails 7045 and7046, for example, extending along the longitudinal axis of the frame7041 which, as described in greater detail further below, can beconfigured to guide one or more anvils, or cams, which can engage anddeform the staple legs of the staples 6220 after the staple legs 6221 ofthe staples 6220 have passed through the retention matrix. In at leastone such embodiment, the guide rails 7045 and 7046 can comprise a guidewire or cable which extends along a top portion or surface of the frame7041, around a distal post 7047, and back along the top portion orsurface of the frame 7041, for example. In various embodiments, asmentioned above and referring primarily now to FIGS. 163 and 165, thesecond jaw 7040 can further comprise one or more anvils, or cams, suchas first anvil 7050 and second anvil 7060, for example, which can bemoved longitudinally along the second jaw 7040 in order to deform thelegs of the staples 6220 after they have passed through the retentionmatrix. In at least one embodiment, the surgical stapler 7000 canfurther comprise a first anvil driver, or actuator, 7051 connected toand/or operably coupled to the first anvil 7050 which can be configuredto pull the first anvil 7050 proximally and/or push the first anvil 7050distally. Similarly, in at least one embodiment, the surgical stapler7000 can further comprise a second anvil driver, or actuator, connectedto and/or operably coupled to the second anvil 7060 which can beconfigured to push the second anvil 7060 distally and/or pull the secondanvil 7060 proximally. In various embodiments, the first anvil 7050 cancomprise guide slots 7052 and the second anvil 7060 can comprise guideslots 7062 which can each be configured to slidably receive guide rail7045 or guide rail 7046 therein. In at least one such embodiment, theguide rails 7045 and 7046 can be closely received within the guide slots7052 and 7062 such that relative lateral, or side-to-side, movementtherebetween can be prevented, or at least limited.

In certain embodiments, further to the above, the first anvil 7050 canbe pulled proximally and the second anvil 7060 can be pulled distally.In at least one embodiment, referring to FIG. 161, the guide rails 7045and 7046 and the distal post 7047 can comprise a pulley systemconfigured to pull the second anvil 7060 distally and/or pull the secondanvil 7060 proximally. In at least one such embodiment, the guide rail7045 and the guide rail 7046 can comprise a continuous wire or cableextending around the distal post 7047, wherein a portion of thecontinuous wire can be pulled in order to cycle the wire around thedistal post 7047. In various embodiments, the guide rail 7046, forexample, can be mounted to the second anvil 7060 such that, when thecontinuous cable is cycled in a first direction, the second anvil 7060can be pulled distally toward the distal end 7048 of the jaw 7040 and,when the continuous cable is cycled in a second, or opposite, direction,the second anvil 7060 can be pulled proximally toward the proximal end7049. In at least one embodiment, referring now to FIG. 163, the guiderail 7046 can be secured within a guide slot 7062 such that a pullingforce can be transmitted therebetween. In at least one such embodiment,the guide rail 7045 can be configured to slide within the other guideslot 7062. In various embodiments, the first anvil 7050 may operateindependently of the second anvil 7060 and the pulley system and theguide slots 7052 defined in the first anvil 7050 may be configured toslidably receive the guide rails 7045 and 7046 such that relativemovement is permitted therebetween. In various embodiments, thecontinuous cable comprising guide rails 7045 and 7046 can besufficiently flexible in order to accommodate the opening and closing ofthe top jaw 7040. The continuous cable can also be sufficiently flexiblein order to accommodate the vertical movement of the second anvil 7060toward and away from the bottom jaw 7030, which is described in greaterdetail further below.

In various embodiments, referring again to FIGS. 163 and 165, the firstanvil 7050 can comprise cam followers 7055 extending therefrom which canbe configured to ride in one or more cam slots, or guide slots, such ascam slot 7070 (FIG. 166), for example, defined in the frame 7041 of thesecond jaw 7040. More particularly, in at least one embodiment, theframe 7041 can comprise a first cam slot 7070 extending longitudinallyalong a first side of the frame 7041 and a second cam 7070 extendinglongitudinally along a second, or opposite, side of the frame 7041,wherein the cam followers 7055 extending from a first side of the firstanvil 7050 can ride in the first cam slot 7070 and the cam followers7055 extending from a second side of the first anvil 7050 can ride inthe second cam slot 7070. In at least one such embodiment, the contoursof each cam slot 7070 can be identical, or at least substantiallyidentical, and can be aligned, or at least substantially aligned, withone another. Similarly, in various embodiments, the second anvil 7060can comprise cam followers 7065 extending therefrom which can beconfigured to ride in the cam slots 7070 (FIG. 166) defined in the frame7041 of the second jaw 7040. More particularly, in at least oneembodiment, the cam followers 7065 extending from a first side of thesecond anvil 7060 can ride in the first cam slot 7070 and the camfollowers 7065 extending from a second side of the second anvil 7060 canride in the second cam slot 7070. In use, the cam followers 7055 of thefirst anvil 7050 and the cam followers 7065 of the second anvil 7060 canslide within the cam slots 7070 such that first anvil 7050 and thesecond anvil 7060 follow the contours of the cam slots 7070 as the firstanvil 7050 and the second anvil 7060 are pulled proximally and/or pusheddistally. In various embodiments, each cam slot 7070 can comprise aplurality of dwell, or upper, portions 7071 and a plurality of driver,or lower, portions 7072 which can be configured to move the anvils 7050and 7060 vertically, i.e., toward and away from the bottom jaw 7030, atthe same time that the anvils 7050 and 7060 are being movedlongitudinally, i.e., between the distal end 7048 and the proximal end7049 of the frame 7041, as described in greater detail further below.

When the surgical stapler 7000 is in an unfired condition, referring toFIG. 166, the first anvil 7050 can be positioned at the distal end 7048of the frame 7041 and the second anvil 7060 can be positioned at theproximal end 7049 of the frame 7041; furthermore, referring now to FIG.167, the staples 6220 positioned in the first jaw 7030 may not yet beinserted into the tissue T and/or the retention matrix positionedthereabove when the surgical stapler 7000 is in an unfired condition. Inuse, referring now to FIG. 168, the staples 6220 can be driven upwardlywithin the staple cavities 7033 of a staple cartridge by the stapledrivers 7012 and, in addition, the first anvil 7050 can be movedproximally from the distal end 7048 of the frame 7041 toward the distalend 7049 in order to engage the staple legs 6221 of the staples 6220. Inat least one embodiment, the staples 6220 can be driven upwardly beforethe first anvil 7050 is engaged with the staple legs 6221 thereof. Invarious embodiments, all of the staples 6220 may be deployed upwardly bythe sled 7010 before the first anvil 7050 is advanced into contact withthe staple legs 6221 or, alternatively, the sled 7010 may be movedproximally at the same time that the first anvil 7050 is movedproximally, although the sled 7010 may sufficiently lead the first anvil7050 in order to deploy the staples 6220 ahead of the first anvil 7050.In various embodiments, as illustrated in FIG. 168, the cam slots 7070can be configured and arranged such that the forming surfaces, such asforming, or camming, surfaces 7053 and 7054, for example, of the firstcam 7050 can contact at least some of the staple legs 6221 when thefirst cam 7050 is passing through a dwell, or upper, position. Invarious circumstances, the cam followers 7055 of the first anvil 7050can each be positioned in a dwell portion 7071 of the cam slots 7070such that the forming surfaces 7053 and 7054 are in a raised positionand such that the staple legs 6221 are only partially deformed when theanvil 7050 passes thereby in the dwell position. As the first cam 7050is moved further along the cam slots 7070, as illustrated in FIG. 169,the cam followers 7055 of the first anvil 7050 can be driven intodriven, or lower, portions 7072 of the cam slots 7070 such that theforming surfaces 7053 and 7054 are moved vertically downwardly towardthe staple legs 6021 in order to drive the staple legs 6021 into theirfinally formed configurations. Thereafter, as the first anvil 7050 isprogressed further along the cam slots 7070, the first anvil 7050 can bedriven vertically upwardly into another set of dwell portions 7071 ofthe cam slots 7070. As illustrated in FIGS. 168 and 169, the reader willnote that the first anvil 7050 may only engage some of the staple legsand not others. In at least one such embodiment, the first anvil 7050can be configured to only deform a group of staple legs comprising thedistal staple legs 6221 of the staples 6220, for example. In at leastone such embodiment, the first anvil 7050 can be configured to deformthe distal staple legs 6221 toward the center of the staples 6220. Invarious embodiments, each proximal staple leg 6221 can be contactedtwice by the first anvil 7050, i.e., by a first forming surface 7053 andby a second forming surface 7054 aligned with the first forming surface7053. In at least one such embodiment, the first forming surfaces 7053can deform the distal staple legs 6221 into a partially-deformedconfiguration when the first anvil 7050 is in a dwell, or upper,position and the second forming surfaces 7054 can deform the distalstaple legs 6221 into a fully-formed configuration when the first anvil7050 is moved into a driven, or lower, position. In various embodiments,referring now to FIGS. 163 and 164, the first anvil 7050 can comprise aplurality of first forming surfaces 7053 and a plurality of secondforming surfaces 7054 in order to deform the distal staple legs 6221 ofstaples 6220 when the staple legs 6221 are arranged in more than one rowor line. In various embodiments, as described in greater detail furtherbelow, the proximal staple legs 6221 of the staples 6020 can be deformedby the second anvil 7060, for example.

In various embodiments, further to the above, the first anvil 7050 canbe moved from the distal end 7048 of the frame 7041 to the proximal end7049 in order to deform all of the distal staple legs 6221 of thestaples 6220. As the reader will note, the first anvil 7050 can be movedup and down relative to the undeformed proximal staple legs 6221 and, inorder to accommodate such relative movement, in various embodiments, thefirst anvil 7050 can comprise one or more clearance slots 7057 (FIG.165) which can be configured to receive the unbent proximal staple legs6221 as the first anvil 7050 bends the distal staple legs 6221.Similarly, referring again to FIG. 163, the second anvil 7060 cancomprise a clearance slot 7067 which can be configured to accommodatethe vertical movement of the first cam actuator 7051 which moves up anddown as the first anvil 7050 is moved between its dwell and drivenpositions as described above. After all of the distal staple legs 6221have been bent, in at least one embodiment, the second anvil 7060 can bemoved from the proximal end 7049 of the frame 7041 to the distal end7048 by the anvil actuator 7061. Similar to the above, referring now toFIG. 170, the cam followers 7065 of the second anvil 7060 can slidewithin the cam slots 7070 such that the second anvil 7060 is movedbetween dwell, or upper, positions and driven, or lower, positions inorder to deform the proximal staple legs 6221 inwardly toward thecenters of the staples 6220, for example. Similar to the above, thesecond anvil 7060 can comprise a plurality of first forming, or camming,surfaces 7063 and a plurality of second forming, or camming, surfaces7064 which can each be configured to at least partially deform and/orcompletely deform one or more of the proximal staple legs 6021.Referring again to FIG. 164, the second anvil 7060 can comprise aplurality of first forming surface 7063 and a plurality of secondforming surfaces 7064 which can be configured to deform the proximalstaple legs 6221 of staples 6220 arranged in a plurality of rows, orlines, for example. As also illustrated in FIG. 164, the first formingsurfaces 7063 and the second forming surfaces 7064 of the second anvil7060 may not be aligned with the first forming surfaces 7053 and thesecond forming surfaces 7054 of the first anvil 7050 wherein, as aresult, the proximal legs 6221 of the staples 6220 may be positioned indifferent rows, or lines, than the distal legs 6221 of the staples 6220.As the reader will also note, the second anvil 7060 can push the firstanvil 7050 as the second anvil 7060 is moved distally. In at least onesuch embodiment, the second anvil 7060 can push the first anvil 7050back into the distal end 7048 of the frame 7041 such that the firstanvil 7050 can be returned to its initial, or unfired, position. Afterall of the proximal staple legs 6221 of the staples 6220 have beendeformed, the second anvil 7060 can be retracted proximally and returnedto its initial, or unfired, position. In this way, the surgical stapler7000 can be reset such that a new staple cartridge can be positioned inthe first jaw 7030 and a new retention matrix can be positioned in thesecond jaw 7040 in order to use the surgical stapler 7000 once again.

In various embodiments, as described above, a surgical stapler cancomprise two or more anvils which can travel longitudinally in order toengage the legs of a plurality of staples in a transverse direction. Incertain embodiments, a surgical stapler can comprise an anvil which ismoved proximally, for example, in order to deform a first group ofstaple legs and distally, for example, in order to deform a second groupof staple legs. In at least one such embodiment, such an anvil cancomprise forming surfaces facing proximally and forming surfaces facingdistally, for example.

In various embodiments, referring now to FIG. 171, an anvil, such asanvil 7140, for example, can comprise a bottom, or tissue-contacting,surface 7141 and a plurality of forming pockets 7142 defined therein. Inat least one embodiment, the anvil 7140 can comprise more than oneplate, such as pocket plates 7143, for example, which can be welded intoa frame 7144. In at least one such embodiment, each pocket plate 7143can be positioned in a plate channel 7145 in the frame 7144 and weldedto the frame 7144 through a weld slot 7146 extending through the frame7144 in order to form a longitudinal weld 7147. In variouscircumstances, the longitudinal weld 7147 can comprise a continuous weldextending along the entire length of the weld slot 7146 or a series ofspaced-apart spot welds extending along the length thereof, for example.In various embodiments, each pocket plate 7143 can comprise two or moreplate portions that have been welded together. In at least one suchembodiment, each pocket plate 7143 can comprise a first plate portion7143 a and a second plate portion 7143 b which can be welded togetheralong a seam 7148. In various embodiments, the first plate portion 7143a and the second plate portion 7143 b of each plate 7143 can be weldedtogether before the plates 7143 are welded into the plate channels 7145in the frame 7144. In at least one such embodiment, the first plateportion 7143 a and the second plate portion 7143 b can compriseco-operating profiles, such as the toothed profiles illustrated in FIG.171, for example, which can be fitted together to form a tight seam7148. In at least one embodiment, each plate 7143 can comprise a heightof approximately 0.02″, for example, which can be taller than the depthof the plate channels 7145 such that the tissue-contacting surfaces 7141thereof extend from the frame 7044 of the anvil 7040. In certainembodiments, referring now to FIG. 172, the plates 7143 can be connectedtogether by at least one weld 7149 at the distal ends of the plates7143, for example.

As illustrated in FIGS. 171 and 172, each pocket plate 7143 can comprisea plurality of forming pockets 7142 defined therein. In variousembodiments, the forming pockets 7142 can be formed in the plates 7143by any suitable manufacturing process, such as a grinding process and/orelectrode-burning process, for example. In at least one such embodiment,referring now to FIGS. 173 and 174, each forming pocket 7142 can bemanufactured by first forming a deep well 7150, then forming an arcuateor curved surface 7151 surrounding the deep well 7150, and then forminga staple leg guide groove 7152 in the curved surface 7151, for example.In various other embodiments, these steps can be performed in anysuitable order. In various embodiments, referring now to FIG. 175, thestaple forming pockets 7142 can be formed such that the inner edges 7153of the forming pockets are separated by a consistent, or at leastsubstantially consistent, gap 7154. In at least one such embodiment, thegap 7154 can be approximately 0.008″, for example. Furthermore, in atleast one such embodiment, the forming pockets 7142 can be positionedalong two or more rows, or lines, the centerlines of which can beseparated by a consistent, or at least substantially consistent, spacing7155. In at least one such embodiment, the spacing 7155 between thecenterlines can be approximately 0.035″, for example. In variousembodiments, referring again to FIG. 175, each forming pocket 7142 cantaper between a narrow width 7156 and a wide width 7157. In at least onesuch embodiment, the narrow width 7156 can be approximately 0.045″ andthe wide width 7157 can be approximately 0.075″, for example. In variousembodiments, the plates 7143 can be comprised of the same material asthe frame 7144. In at least one such embodiment, the plates 7143 and theframe 7144 can both be comprised of stainless steel, such as a 300series or a 400 series stainless steel, for example, and/or titanium,for example. In various other embodiments, the plates 7143 and the frame7144 can be comprised of different materials. In at least one suchembodiment, the plates 7143 can be comprised of a ceramic material, forexample, and the frame 7144 can be comprised of a stainless steel and/ortitanium, for example. In various circumstances, depending on thematerials used, at least one brazing process could be used to secure theplates 7143 in the frame 7144 in addition to or in lieu of the weldingprocesses described above, for example.

In various embodiments, referring now to FIGS. 176-178, an anvil 7240can comprise a frame 7244 and a plurality of pocket plates 7243 whichcan be inserted into the frame 7244. Similar to the above, each pocketplate 7243 can comprise a plurality of forming pockets 7242 definedtherein. In at least one embodiment, the anvil frame 7244 can compriseretention slots 7246 defined therein which can each be configured toreceive a retention rail 7247 extending from a pocket plate 7243. Inorder to assemble the pocket plates 7243 to the anvil frame 7244, theside walls 7245 of the anvil frame 7244 can be flexed or splayedoutwardly, as illustrated in FIG. 177, in order to widen the retentionslots 7246 such that each retention slot 7246 can receive a retentionrail 7247 of a pocket plate 7243 therein. Once the retention rails 7247have been positioned in the retention slots 7246, the side walls 7245can be released, as illustrated in FIG. 178, thereby allowing the frame7244 to resiliently contract and/or return to its unflexed state. Insuch circumstances, the retention slots 7246 can contract and therebycapture the retention rails 7247 therein. In certain embodiments, theretention rails 7247 and/or the retention slots 7246 can comprise one ormore co-operating tapered surfaces which, after the flexed retentionslots 7246 have been released, can form a taper-lock engagement whichcan retain the retention rails 7247 in the retention slots 7246. Similarto the above, the pocket plates 7243 can be comprised of the samematerial as or a different material than the frame 7244. In at least onesuch embodiment, the plates 7243 can be comprised of a ceramic material,for example, and the frame 7244 can be comprised of a stainless steeland/or titanium, for example. In various circumstances, depending on thematerials used, at least one brazing process and/or at least one weldingprocess, for example, could be used to secure the plates 7243 in theframe 7244.

In FIGS. 179 and 180, a surgical stapling and severing instrument 8010can comprise an anvil 8014 which may be repeatably opened and closedabout its pivotal attachment to an elongate staple channel 8016. Astaple applying assembly 8012 can comprise the anvil 8014 and thechannel 8016, wherein the assembly 8012 can be proximally attached tothe elongate shaft 8018 forming an implement portion 8022. When thestaple applying assembly 8012 is closed, or at least substantiallyclosed, the implement portion 8022 can present a sufficiently smallcross-section suitable for inserting the staple applying assembly 8012through a trocar. In various embodiments, the assembly 8012 can bemanipulated by a handle 8020 connected to the shaft 8018. The handle8020 can comprise user controls such as a rotation knob 8030 thatrotates the elongate shaft 8018 and staple applying assembly 8012 abouta longitudinal axis of the shaft 8018. A closure trigger 8026, which canpivot in front of a pistol grip 8036 about a closure trigger pin 8152(FIG. 181) engaged laterally across the handle housing 8154, can bedepressed to close the staple applying assembly 8012. In variousembodiments, a closure release button 8038 can be outwardly presented onthe handle 8020 when the closure trigger 8026 is clamped such that therelease button 8038 can be depressed to unclamp the closure trigger 8026and open the staple applying assembly 8012, as described in greaterdetail below. A firing trigger 8034, which can pivot in front of theclosure trigger 8026, can cause the staple applying assembly 8012 tosimultaneously sever and staple tissue clamped therein. In variouscircumstances, as described in greater detail below, multiple firingstrokes can be employed using the firing trigger 8034 to reduce theamount of force required to be applied by the surgeon's hand per stroke.In certain embodiments, the handle 8020 can comprise rotatable rightand/or left indicator wheels 8040, 8041 (FIG. 181) which can indicatethe firing progress. For instance, full firing travel may require threefull firing strokes of firing trigger 8034 and thus the indicator wheels8040, 8041 can rotate up to one-third of a revolution each per stroke offiring trigger 8034. As described in greater detail below, a manualfiring release lever 8042 can allow the firing system to be retractedbefore full firing travel has been completed, if desired, and, inaddition, the firing release lever 8042 can allow a surgeon, or otherclinician, to retract the firing system in the event that the firingsystem binds and/or fails.

With reference to FIGS. 179 and 181, the elongate shaft 8018 cancomprise an outer structure including a longitudinally reciprocatingclosure tube 8024 that pivots the anvil 8014 toward its close positionin response to the proximal depression of the closure trigger 8026 ofhandle 8020. The elongate channel 8018 can be connected to the handle8020 by a frame 8028 (FIG. 181) that is internal to the closure tube8024. The frame 8028 can be rotatably engaged to the handle 8020 so thatthe rotation of the rotation knob 8030 (FIG. 179) can rotate theimplement portion 8022. With particular reference to FIG. 181, therotation knob 8030 can be comprised of two half-shells which can includeone or more inward projections 8031 that can extend through one or moreelongate side openings 8070 in the closure tube 8024 and engage theframe 8028. As a result of the above, the rotation knob 8030 and theframe 8028 can be rotated together, or synchronously, such that therotated position of knob 8030 determines the rotated position of theimplement portion 8022. In various embodiments, the longitudinal lengthof the longer opening 8070 is sufficiently long to allow thelongitudinal closure motion, and opening motion, of the closure tube8024. With regard to generating the closure motion of closure tube 8024,referring primarily to FIGS. 181 and 183, an upper portion 8160 of theclosure trigger 8026 can push forward a closure yoke 8162 via a closurelink 8164. The closure link 8164 is pivotally attached at its distal endby a closure yoke pin 8166 to the closure yoke 8162 and is pivotallyattached at its proximal end by a closure link pin 8168. In variousembodiments, the closure trigger 8026 can be urged to an open positionby a closure trigger tension spring 8246 that is connected proximally tothe upper portion 8160 of the closure trigger 8026 and a handle housing8154 formed by right and left half shells 8156, 8158. The tension forceapplied by the tension spring 8246 can be overcome by a closing forceapplied to the closure trigger 8026 in order to advance the yoke 8162,closure link 8164, and the closure tube 8024 distally.

As the closure trigger 8026 is actuated, or depressed, as describedabove, the closure release button 8038 can be positioned such that thesurgeon, or other clinician, can push the closure release button 8038,if desired, and allow the closure trigger 8026, and the rest of thesurgical instrument, to return to an unactuated state. In variousembodiments, the closure release button 8038 can be connected to apivoting locking arm 8172 by a central lateral pivot 8173 such thatmotion can be transferred between the release button 8038 and thelocking arm 8172. Referring again to FIG. 181, a compression spring 8174can bias the closure release button 8038 proximally, i.e., clockwiseabout the central lateral pivot 8173 as viewed from the right and theupper portion 8160 of the closure trigger 8026 can include a proximalcrest 8170 with an aft notch 8171. As the closure trigger 8026 isdepressed, the pivoting locking arm 8172 can ride upon the proximalcrest 8170 and when the closure trigger 8026 reaches its fully depressedposition, it should be appreciated that the aft notch 8171 is presentedbelow the pivoting locking arm 8172 which drops into and locks againstthe aft notch 8171 under the urging of the compression spring 8174. Atsuch point, manual depression of the closure release button 8038 rotatesthe pivoting locking arm 8172 upward and out of aft notch 8171 therebyunlocking the closure trigger 8026 and allowing the closure trigger 8026to be returned to its unclamped position.

Once the closure trigger 8026 is proximally clamped, as discussed above,the firing trigger 8034 can be drawn toward the pistol grip 8036 inorder to advance a firing rod 8032 distally from the handle 8020. Invarious embodiments, the firing trigger 8034 can pivot about a firingtrigger pin 8202 that laterally traverses and is engaged with the rightand left half shells 8156, 8158 of the handle 8020. The firing trigger8034, when actuated, can advance a linked transmission firing mechanism8150. The linked transmission firing mechanism 8150 can be urged into aretracted, unfired, position by a spring 8184 that is, one, attached tothe pistol grip 8036 of the handle 8020 and, two, attached to one of thelinks, for example, of the linked transmission firing mechanism 8150 asdescribed in greater detail below. The spring 8184 can comprise anonmoving end 8186 connected to the housing 8154 and a moving end 8188connected to a proximal end 8190 of a steel band 8192. Adistally-disposed end 8194 of the steel band 8192 can be attached to anattachment feature 8195 on a front link 8196 a of a plurality of links8196 a-8196 d that form a linked rack 8200. Linked rack 8200 can beflexible such that it can readily retract into the pistol grip 8036 andminimize the length of the handle 8020 and yet form a straight rigidrack assembly that may transfer a significant firing force to and/orthrough the firing rod 8032. As described in greater detail below, thefiring trigger 8034 can be engaged with a first link 8196 a during afirst actuation of the firing trigger 8034, engaged with a second link8196 b during a second actuation of the firing trigger 8034, engagedwith a third link 8196 c during a third actuation of the firing trigger8034, and engaged with a fourth link 8196 d during a fourth actuation ofthe firing trigger 8034, wherein each actuation of the firing trigger8034 can advance the linked rack 8200 distally an incremental amount. Invarious embodiments, further to the above, the multiple strokes offiring trigger 1034 can rotate the right and left indicator gauge wheels1040, 1041 to indicate the distance in which the linked rack 8200 hasbeen advanced.

Referring now to FIGS. 181 and 183, an anti-backup mechanism 8250 canprevent the combination tension/compression spring 8184 from retractingthe linked rack 8200 between firing strokes. In various embodiments, acoupling slide tube 8131 abuts the first link 8196 a and connects to thefiring rod 8032 to communicate the firing motion. The firing rod 8032extends proximally out of a proximal end of the frame 8028 and through athrough hole 8408 of an anti-backup plate 8266. The through hole 8408 issized to slidingly receive the firing rod 8032 when perpendicularlyaligned but to bind when tipped. A lower tab attachment 8271 extendsproximally from a lower lip of the proximal end of the frame 8028,extending through an aperture 8269 on a lower edge of the anti-backupplate 8266. This lower tab attachment 8271 draws the lower portion ofthe anti-backup plate 8266 proximate to the frame 8028 so that theanti-backup plate 8266 is perpendicular when the firing rod 8032 isdistally advanced and allowed to tip top aft into a binding state whenthe firing rod 8032 attempts to retract. An anti-backup compressionspring 8264 is distally constrained by the proximal end of the frame8028 and proximally abuts a top portion of the anti-backup plate 8266,biasing the anti-backup plate 8266 to a locking state. Opposing thespring bias, an anti-backup cam tube 8268 slidingly encompasses thecoupling slide tube 8131 and abuts the anti-backup plate 8266. Aproximally projecting anti-backup yoke 8256 attached to the anti-backupcam tube 8268 extends overtop of the closure yoke 8162.

Referring to FIG. 181, a link triggered automatic retraction mechanism8289 is incorporated into the surgical stapling and severing instrument8010 to cause knife retraction at the end of full firing travel. To thatend, the distal link 8196 d includes a tang 8290 that projects upwardlywhen the distal link 8196 d is advanced into rack channel 8291 (FIG.181) formed in the closure yoke 8162. This tang 8290 is aligned toactivate a bottom proximal cam 8292 on an anti-backup release lever 8248(FIG. 186). With particular reference to FIGS. 186 and 187, structuresformed in the right and left half shells 8156, 8158 constrain movementof the anti-backup release lever 8248. A pin receptacle 8296 andcircular pin 8293 formed respectively between right and left half shells8156, 8158 is received through a longitudinally elongate aperture 8294formed in the anti-backup release lever 8248 distal to the bottomproximal cam 8292, thus allowing longitudinal translation as well asrotation about the circular pin 8293. In the right half shell 8156, aproximally open channel 8295 includes a proximal horizontal portion 8295a that communicates with an upwardly and distally angled portion 8295 bthat receives a rightward aft pin 8297 (FIG. 187) near the proximal endof the anti-backup release lever 8248, thus imparting an upward rotationas the anti-backup release lever 8248 reaches the distal most portion ofits translation. A blocking structure formed in the right half shell8156 proximal to the anti-backup release lever 8248 prevents proximalmovement thereof once assembled to maintain rightward aft pin 8297 inthe proximally open channel 8295.

Further to the above, as depicted in FIGS. 187 and 188, a distal end8254 of the anti-backup release lever 8248 thus is urged distally anddownwardly, causing a rightward front pin 8298 to drop into distallyopen step structure 8299 formed in the right half shell 8156, which isurged into this engagement by a compression spring 8300 (FIG. 188)hooked to a leftward hook 8301 on the anti-backup release lever 8248between the rightward front pin 8298 and the longitudinally elongateaperture 8294. The other end of the compression spring 8300 is attachedto a hook 8302 (FIGS. 186, 188, 189) formed in the right half shell 8156in a more proximal and lower position just above the closure yoke 8266.The compression spring 8300 thus pulls the distal end 8254 of theanti-backup release lever 8248 down and aft, which results in therightward front pin 8298 locking into the distally open step structure8299 when distally advanced. Thus, once tripped, referring to FIG. 189,the anti-backup release lever 8248 remains forward holding theanti-backup plate 8266 perpendicularly and thus allowing the linked rack8200 to be retracted. When the closure yoke 8266 is subsequentlyretracted when unclamping the end effector 8012, an upwardly projectingreset tang 8303 on the closure yoke 8266 contacts a bottom distal cam8305 of the anti-backup release lever 8248, lifting the rightward frontpin 8298 out of the distally open step structure 8299 so that theanti-backup compression spring 8264 can proximally push the anti-backupcam tube 8268 and the anti-backup release lever 8248 to their retractedpositions (FIG. 186).

In various embodiments, referring to FIGS. 179 and 189, the firingtrigger 8034 can be operably engaged to the linked rack 8200 in anysuitable manner. With particular reference to FIGS. 180 and 185, thefiring trigger 8034 pivots about a firing trigger pin 8202 that isconnected to the housing 8154. An upper portion 8204 of the firingtrigger 8034 moves distally about the firing trigger pin 8202 as thefiring trigger 8034 is depressed towards pistol grip 8036, stretching aproximally placed firing trigger tension spring 8206 (FIG. 181)proximally connected between the upper portion 8204 of the firingtrigger 8034 and the housing 8154. The upper portion 8204 of the firingtrigger 8034 engages the linked rack 8200 during each firing triggerdepression via a spring biased side pawl mechanism 8210. When the firingtrigger is released, the side pawl mechanism is disengaged from thelinked rack 8200 and the firing trigger can be returned to anundepressed, or unfired, position. In use, a ramped right-side trackformed by a proximally and rightwardly facing beveled surface 8284 ineach of the links 8196 a-8196 d is engaged by a side pawl assembly 8285.In particular, a pawl slide 8270 (FIGS. 181 and 183) has right and leftlower guides 8272 that slide respectively in a left track 8274 (FIG.181) formed in the closure yoke 8266 below the rack channel 8291 and aright track 8275 in a closure yoke rail 8276 that parallels rack channel8291 and is attached to a rack channel cover 8277 that closes arightwardly open portion of the rack channel 8291 in the closure yoke8266 that is distal to the travel of the pawl slide 8270. In FIGS. 181,182, and 185, a compression spring 8278 is attached between a hook 8279on a top proximal position on the closure yoke rail 8276 and a hook 8280on a distal right-side of the pawl slide 8270, which keeps the pawlslide 8270 drawn proximally into contact with the upper portion 8204 ofthe firing trigger 8034.

With particular reference to FIG. 181, a pawl block 8318 sits on thepawl slide 8270 pivoting about a vertical aft pin 8320 that passesthrough a left proximal corner of pawl block 8318 and pawl slide 8270. Akick-out block recess 8322 is formed on a distal portion of a topsurface of the block 8318 to receive a kick-out block 8324 pivotallypinned therein by a vertical pin 8326 whose bottom tip extends into apawl spring recess 8328 on a top surface of the pawl slide 8270. A pawlspring 8330 in the pawl spring recess 8328 extends to the right of thevertical front pin 8326 urging the pawl block 8318 to rotatecounterclockwise when viewed from above into engagement with the rampedright-side track 8282. A small coil spring 8332 in the kick-out blockrecess 8322 urges the kick-out block 8324 to rotate clockwise whenviewed from above, its proximal end urged into contact with a contouredlip 8334 formed in the closure yoke 8266 above the rack channel 8291. Asshown in FIG. 184, the stronger mechanical advantage of the pawl spring8330 over the small coil spring 8332 means that the pawl block 8318tends toward engagement with the kick-out block 8324 rotated clockwise.In FIG. 185, as the firing trigger 8034 is fully depressed and begins tobe release, the kick-out block 8324 encounters a ridge 8336 in thecontoured lip 8334 as the pawl slide 8270 retracts, forcing the kick-outblock 8324 to rotate clockwise when viewed from above and therebykicking out the pawl block 8318 from engagement with the linked rack8200. The shape of the kick-out block recess 8322 stops the clockwiserotation of the kick-out block 8324 to a perpendicular orientation tothe contoured lip 8334 maintaining this disengagement during the fullretraction and thereby eliminating a ratcheting noise.

In FIGS. 181, 183, 190, and 195, the surgical stapling and severinginstrument 8010 can include a manual retraction mechanism 8500 thatprovides for a manual release of the firing mechanism, manualretraction, and in one version (FIGS. 196-202) further performsautomatic retraction at the end of full firing travel. Referring now toFIGS. 181, 190, and 191, in particular, a front idler gear 8220 isengaged with a toothed upper, left surface 8222 of the linked rack 8200wherein the front idler gear 8220 also engages an aft idler gear 8230having a smaller right-side ratchet gear 8231. Both the front idler gear8220 and aft idler gear 8230 are rotatably connected to the handlehousing 8154 respectively on front idler axle 8232 and aft idler axle8234. Each end of the aft axle 8232 extend through the respective rightand left housing half shells 8156, 8158 and are attached to the left andright indicator gauge wheels 8040, 8041 and, since the aft axle 8234 isfree spinning in the handle housing 8154 and has a keyed engagement tothe aft gear 8230, the indicator gauge wheels 8040, 8041 rotate with theaft gear 8230. The gear relationship between the linked rack 8200, idlergear 8220 and aft gear 8230 may be advantageously selected so that thetoothed upper surface 8222 has tooth dimensions that are suitably strongand that the aft gear 8230 makes no more than one revolution during thefull firing travel of the linked transmission firing mechanism 8150. Inaddition to gear mechanism 8502 visually indicating the firing travel,or progress, the gear mechanism 8502 can also be used to manual retractthe knife. In various embodiments, the smaller right-side ratchet gear8231 of the aft idler gear 8230 extends into a hub 8506 of the manualretraction lever 8042, specifically aligned with a verticallongitudinally-aligned slot 8508 (FIG. 190) bisecting the hub 8506. Alateral through hole 8510 of the hub 8506 communicates with an upperrecess 8512. A front portion 8514 is shaped to receive a proximallydirected locking pawl 8516 that pivots about a rightward lateral pin8518 formed in a distal end of the upper recess 8512. An aft portion8520 is shaped to receive an L-shaped spring tab 8522 that urges thelocking pawl 8516 downward into engagement with the right-side smallerratchet gear 8231. A hold-up structure 8524 (FIGS. 186 and 193) projectsfrom the right half shell 8156 into the upper recess 8512 holding up thelocking pawl 8516 from engaging the smaller right-side ratchet gear 8231when the manual retraction lever 8042 is down (FIG. 193). A coil spring8525 (FIG. 181) urges the manual retraction lever 8042 down.

In use, as depicted in FIGS. 192 and 193, the combinationtension/compression spring 8184 may become disconnected with the linkedrack distally positioned. In FIGS. 194 and 195, as the manual retractionlever 8042 is raised, the locking pawl 8516 rotates clockwise and nolonger is held up by the hold-up structure 8524 and engages the smallerright-side ratcheting gear 8231, rotating the aft idler gear 8230clockwise when viewed from the left. Thus, the forward idler gear 8220responds counterclockwise retracting the linked rack 8200. In addition,a rightward curved ridge 8510 projects out from the hub 8506, sized tocontact and distally move the anti-backup release lever 8248 to releasethe anti-backup mechanism 8250 as the manual retraction lever 8042 isrotated.

In FIGS. 196-202, an automatic retraction mechanism 8600 for a surgicalstapling and severing instrument 8010 a can incorporate automaticretraction at the end of full firing travel into a front idler gear 8220a having a tooth 8602 that moves within a circular groove 8604 in a camwheel 8606 until encountering a blockage 8608 after nearly a fullrotation corresponding to three firing strokes. In such circumstances,rightward ridge 8610 is rotated upward into contact a bottom cam recess8612 to distally move an anti-backup release lever 8248 a. Withparticular reference to FIG. 197, the anti-backup release lever 8248 aincludes the distal end 8254 that operates as previously described. Thecircular pin 8293 and pin receptacle 8296 formed between right and lefthalf shells 8156, 8158 is received through a generally rectangularaperture 8294 a formed in the anti-backup release lever 8248 a aft ofthe bottom cam 8192, thus allowing longitudinal translation as well asdownward locking motion of the distal end 8254 of the anti-backuprelease lever 8248 a. In the right half shell 8156, a horizontalproximally open channel 8295 a receives the rightward aft pin 8297 nearthe proximal end of the anti-backup release lever 8248 a.

In operation, before firing in FIGS. 198, 198A, the linked rack 8200 andthe anti-backup cam tube 8268 are in a retracted position, locking theanti-backup mechanism 8250 as the anti-backup compression spring 8264proximally tips the anti-backup plate 8266. The automatic retractionmechanism 8600 is at an initial state with the anti-backup release lever8248 a retracted with link 8196 a in contact with the forward idler gear8220 a. The tooth 8602 is at a six o'clock position with full travel ofthe circular groove 8604 progressing counterclockwise thereof with therightward ridge 8610 just proximal to the tooth 8602. In FIGS. 199,199A, one firing stroke has occurred moving up one distal link 8196 binto contact with the forward idler gear 8220 a. The tooth 8602 hasprogressed one third of a turn through the circular groove 8604 of theimmobile cam wheel 8606. In FIGS. 200, 200A, a second firing stroke hasoccurred moving up one more link 8196 c into contact with the forwardidler gear 8220 a. The tooth 8602 has progressed two thirds of a turnthrough the circular groove 8604 of the immobile cam wheel 8606. InFIGS. 201, 201A, a third firing stroke has occurred moving up one distallink 8196 d into contact with the forward idler gear 8220 a. The tooth8602 has progressed fully around the circular groove 8604 into contactwith the blockage 8608 initiating counterclockwise rotation (when viewedfrom the right) of the cam wheel 8606 bringing the rightward ridge 8608into contact with the anti-backup release lever 8248 a. In FIG. 202, theanti-backup release lever 8248 a has moved distally in response thereto,locking the rightward front pin 8298 into the distally open stepstructure 8299 and releasing the anti-backup mechanism 8250. Similarsurgical stapling instruments are disclosed in U.S. Pat. No. 7,083,075,which issued on Aug. 1, 2006, the entire disclosure of which isincorporated by reference herein.

Referring to FIG. 203, the staple applying assembly 9012 of a surgicalstapling instrument 9010 accomplishes the functions of clamping ontotissue, driving staples and severing tissue by two distinct motionstransferred longitudinally down the shaft 9016 relative to a shaft frame9070. This shaft frame 9070 is proximally attached to a handle of asurgical stapling instrument and is coupled thereto for rotation about alongitudinal axis. An illustrative multi-stroke handle for the surgicalstapling and severing instrument is described in greater detail in theco-pending and co-owned U.S. patent application entitled SURGICALSTAPLING INSTRUMENT INCORPORATING A MULTISTROKE FIRING POSITIONINDICATOR AND RETRACTION MECHANISM, Ser. No. 10/374,026, the disclosureof which is hereby incorporated by reference in its entirety. Otherapplications consistent with the present invention may incorporate asingle firing stroke, such as described in co-pending and commonly ownedU.S. patent application SURGICAL STAPLING INSTRUMENT HAVING SEPARATEDISTINCT CLOSING AND FIRING SYSTEMS, Ser. No. 10/441,632, the disclosureof which is hereby incorporated by reference in its entirety.

With particular reference to FIG. 204, the distal end of the shaft frame9070 is attached to the staple channel 9018. The anvil 9022 has aproximal pivoting end 9072 that is pivotally received within a proximalend 9074 of the staple channel 9018, just distal to its engagement tothe shaft frame 9070. When the anvil 9022 is pivoted downwardly, theanvil 9022 moves a tissue contacting surface 9028 and forming pockets9026 toward an opposing staple cartridge, described in greater detailfurther below. The pivoting end 9072 of the anvil 9022 includes aclosure feature 9076 proximate but distal to its pivotal attachment withthe staple channel 9018. Thus, a closure tube 9078, whose distal endincludes a horseshoe aperture 9080 that engages this closure feature9076, selectively imparts an opening motion to the anvil 9022 duringproximal longitudinal motion and a closing motion to the anvil 9022during distal longitudinal motion of the closure tube 9078 sliding overthe shaft frame 9070 in response to a closure trigger, similar to theabove. The shaft frame 9070 encompasses and guides a firing motion fromthe handle through a longitudinally reciprocating, two-piece knife andfiring bar 9090. In particular, the shaft frame 9070 includes alongitudinal firing bar slot 9092 that receives a proximal portion ofthe two-piece knife and firing bar 9090, specifically a laminate taperedfiring bar 9094. It should be appreciated that the laminated taperedfiring bar 9094 may be substituted with a solid firing bar and/or anyother suitable materials.

An E-beam 9102 is the distal portion of the two-piece knife and firingbar 9090, which facilitates separate closure and firing as well asspacing of the anvil 9022 from the elongate staple channel 9018 duringfiring. With particular reference to FIGS. 204 and 205, in addition toany attachment treatment such as brazing or an adhesive, the knife andfiring bar 9090 are formed of a female vertical attachment aperture 9104proximally formed in the E-beam 9102 that receives a corresponding maleattachment member 9106 distally presented by the laminated taperedfiring bar 9094, allowing each portion to be formed of a selectedmaterial and process suitable for their disparate functions (e.g.,strength, flexibility, friction). The E-beam 9102 may be advantageouslyformed of a material having suitable material properties for forming apair of top pins 9110, a pair of middle pins 9112 and a bottom pin orfoot 9114, as well as being able to acquire a sharp cutting edge 9116.In addition, integrally formed and proximally projecting top guide 9118and middle guide 9120 bracketing each vertical end of the cutting edge9116 further define a tissue staging area 9122 assisting in guidingtissue to the sharp cutting edge 9116 prior to being severed. The middleguide 9120 also serves to engage and fire the staple applying apparatus9012 by abutting a stepped central member 9124 of a wedge sled 9126(FIG. 206) that effects staple formation by the staple applying assembly9012, as described in greater detail below. Forming these features(e.g., top pins 9110, middle pins 9112, and bottom foot 9114) integrallywith the E-beam 9102 facilitates manufacturing at tighter tolerancesrelative to one another as compared to being assembled from a pluralityof parts, ensuring desired operation during firing and/or effectiveinteraction with various lockout features of the staple applyingassembly 9012.

In FIGS. 207 and 208, the staple applying assembly 9012 is shown open,with the E-beam 9102 fully retracted. During assembly, the lower foot9114 of the E-beam 9102 is dropped through a widened hole 9130 in thestaple channel 9018 and the E-beam 9102 is then advanced such that theE-beam 9102 slides distally along a lower track 9132 formed in thestaple channel 9018. In particular, the lower track 9132 includes anarrow slot 9133 that opens up as a widened slot 9134 on an undersurfaceof the staple channel 9018 to form an inverted T-shape in lateral crosssection, as depicted particularly in FIGS. 208 and 209, whichcommunicates with the widened hole 9130. Once assembled, the componentsproximally coupled to the laminate tapered firing bar 9094 do not allowthe lower foot 9114 to proximally travel again to the widened hole 9130to permit disengagement. Referring to FIG. 210, the laminate taperedfiring bar 9094 facilitates insertion of the staple applying assembly9012 through a trocar. In particular, a more distal, downward projection9136 raises the E-beam 9102 when fully retracted. This is accomplishedby placement of the downward projection 9136 at a point where it camsupwardly on a proximal edge of the widened hole 9130 in the staplechannel 9018. Referring now to FIG. 211, the laminate tapered firing bar9094 also enhances operation of certain lockout features that may beincorporated into the staple channel 9018 by including a more proximalupward projection 9138 that is urged downwardly by the shaft frame 9070during an initial portion of the firing travel. In particular, a lateralbar 9140 is defined between a pair of square apertures 9142 in the shaftframe 9070 (FIG. 204). A clip spring 9144 that encompasses the lateralbar 9140 downwardly urges a portion of the laminate tapered firing bar9094 projecting distally out of the longitudinal firing bar slot 9092,which ensures certain advantageous lockout features are engaged whenappropriate. This urging is more pronounced or confined solely to thatportion of the firing travel when the upward projection 9138 contactsthe clip spring 9144.

In FIGS. 207 and 208, the E-beam 9102 is retracted with the top pins9110 thereof residing within an anvil pocket 9150 near the pivotingproximal end of the anvil 9022. A downwardly open vertical anvil slot9152 (FIG. 203) laterally widens in the anvil 9022 into an anvilinternal track 9154 that captures the top pins 9110 of the E-beam 9102as they distally advance during firing, as depicted in FIGS. 210 and211, affirmatively spacing the anvil 9022 from the staple channel 9018.Thus, with the E-beam 9102 retracted, the surgeon is able to repeatablyopen and close the staple applying assembly 9012 until satisfied withthe placement and orientation of tissue captured therein for staplingand severing, yet the E-beam 9102 assists in proper positioning oftissue even for a staple applying assembly 9012 of reduced diameter andcorrespondingly reduced rigidity. In FIGS. 203, 204, 206, 207, 209, and215, the staple applying assembly 9012 is shown with the replaceablestaple cartridge 9020 that includes the wedge sled 9126. Longitudinallyaligned and parallel plurality of downwardly open wedge slots 9202 (FIG.209) receive respective wedges 9204 integral to the wedge sled 9126. InFIGS. 209-211, the wedge sled 9126 thus cams upwardly a plurality ofstaple drivers 9206 that are vertically slidable within staple driverrecesses 9208. In this illustrative version, each staple driver 9206includes two vertical prongs, each translating upwardly into arespective staple hole 9210, or cavity 9024, to upwardly force out anddeform a staple 9023 resting thereupon against a staple forming surface9214 (FIG. 211) of the anvil 9022. A central firing recess 9216 (FIG.204) defined within the staple cartridge 9020 proximate to the staplechannel 9018 allows the passage of the bottom, horizontal portion 9218(FIG. 206) of the wedge sled 9126 as well as the middle pins 9112 of theE-beam 9102. Specifically, a staple cartridge tray 9220 (FIGS. 204, 209)attaches to and underlies a polymer staple cartridge body 9222 that hasthe staple driver recesses 9208, staple holes 9210, and central firingrecess 9216 formed therein. As staples 9023 are thus formed to eitherside, the sharp cutting edge 9116 enters a vertical through slot 9230passing through the longitudinal axis of the staple cartridge 9020,excepting only a most distal end thereof.

Firing the staple applying assembly 9012 begins as depicted in FIG. 211with the two-piece knife and firing bar 9090 proximally drawn until thedownward projection 9136 cams the middle guide 9120 on the E-beam 9102upward and aft, allowing a new staple cartridge 9020 to be inserted intothe staple channel 9018 when the anvil 9022 is open as depicted in FIGS.203 and 207. In FIG. 212, the two-piece knife and firing bar 9090 hasbeen distally advanced a small distance, allowing the downwardprojection 9136 to drop into the widened hole 9130 of the lower track9132 under the urging of the clip spring 9144 against the upwardprojection 9138 of the laminate tapered firing bar 9094. The middleguide 9120 prevents further downward rotation by resting upon thestepped central member 9124 of the wedge sled 9126, thus maintaining themiddle pin 9112 of the E-beam within the central firing recess 9216. InFIG. 213, the two-piece knife and firing bar 9090 has been distallyfired, advancing the wedge sled 9126 to cause formation of staples 9023while severing tissue 9242 clamped between the anvil 9022 and staplecartridge 9020 with the sharp cutting edge 9116. Thereafter, in FIG.214, the two-piece knife and firing bar 9090 is retracted, leaving thewedge sled 9126 distally positioned. In FIG. 215, the middle pin 9112 isallowed to translate down into a lockout recess 9240 formed in thestaple channel 9018 (also see FIGS. 208, 211). Thus, the operator wouldreceive a tactile indication as the middle pin 9112 encounters thedistal edge of the lockout recess 9240 when the wedge sled 9126 (notshown in FIG. 215) is not proximally positioned (i.e., missing staplecartridge 9020 or spent staple cartridge 9020). Similar surgicalstapling instruments are disclosed in U.S. Pat. No. 7,380,696, whichissued on Jun. 3, 2008, the entire disclosure of which is incorporatedby reference herein.

In various embodiments, as described above, a staple cartridge cancomprise a cartridge body including a plurality of staple cavitiesdefined therein. The cartridge body can comprise a deck and a top decksurface wherein each staple cavity can define an opening in the decksurface. As also described above, a staple can be positioned within eachstaple cavity such that the staples are stored within the cartridge bodyuntil they are ejected therefrom. Prior to being ejected from thecartridge body, in various embodiments, the staples can be containedwith the cartridge body such that the staples do not protrude above thedeck surface. As the staples are positioned below the deck surface, insuch embodiments, the possibility of the staples becoming damaged and/orprematurely contacting the targeted tissue can be reduced. In variouscircumstances, the staples can be moved between an unfired position inwhich they do not protrude from the cartridge body and a fired positionin which they have emerged from the cartridge body and can contact ananvil positioned opposite the staple cartridge. In various embodiments,the anvil, and/or the forming pockets defined within the anvil, can bepositioned a predetermined distance above the deck surface such that, asthe staples are being deployed from the cartridge body, the staples aredeformed to a predetermined formed height. In some circumstances, thethickness of the tissue captured between the anvil and the staplecartridge may vary and, as a result, thicker tissue may be capturedwithin certain staples while thinner tissue may be captured withincertain other staples. In either event, the clamping pressure, or force,applied to the tissue by the staples may vary from staple to staple orvary between a staple on one end of a staple row and a staple on theother end of the staple row, for example. In certain circumstances, thegap between the anvil and the staple cartridge deck can be controlledsuch that the staples apply a certain minimum clamping pressure withineach staple. In some such circumstances, however, significant variationof the clamping pressure within different staples may still exist.

In various embodiments described herein, a staple cartridge can comprisemeans for compensating for the thickness of the tissue captured withinthe staples deployed from the staple cartridge. In various embodiments,referring to FIG. 216, a staple cartridge, such as staple cartridge10000, for example, can include a rigid first portion, such as supportportion 10010, for example, and a compressible second portion, such astissue thickness compensator 10020, for example. In at least oneembodiment, referring primarily to FIG. 218, the support portion 10010can comprise a cartridge body, a top deck surface 10011, and a pluralityof staple cavities 10012 wherein, similar to the above, each staplecavity 10012 can define an opening in the deck surface 10011. A staple10030, for example, can be removably positioned in each staple cavity10012. In at least one such embodiment, referring primarily to FIG. 245and as described in greater detail below, each staple 10030 can comprisea base 10031 and one or more legs 10032 extending from the base 10031.Prior to the staples 10030 being deployed, as also described in greaterdetail below, the bases 10031 of the staples 10030 can be supported bystaple drivers positioned within the support portion 10010 and,concurrently, the legs 10032 of the staples 10030 can be at leastpartially contained within the staple cavities 10012. In variousembodiments, the staples 10030 can be deployed between an unfiredposition and a fired position such that the legs 10032 move through thetissue thickness compensator 10020, penetrate through a top surface ofthe tissue thickness compensator 10020, penetrate the tissue T, andcontact an anvil positioned opposite the staple cartridge 10000. As thelegs 10032 are deformed against the anvil, the legs 10032 of each staple10030 can capture a portion of the tissue thickness compensator 10020and a portion of the tissue T within each staple 10030 and apply acompressive force to the tissue. Further to the above, the legs 10032 ofeach staple 10030 can be deformed downwardly toward the base 10031 ofthe staple to form a staple entrapment area 10039 in which the tissue Tand the tissue thickness compensator 10020 can be captured. In variouscircumstances, the staple entrapment area 10039 can be defined betweenthe inner surfaces of the deformed legs 10032 and the inner surface ofthe base 10031. The size of the entrapment area for a staple can dependon several factors such as the length of the legs, the diameter of thelegs, the width of the base, and/or the extent in which the legs aredeformed, for example.

In previous embodiments, a surgeon was often required to select theappropriate staples having the appropriate staple height for the tissuebeing stapled. For example, a surgeon could select tall staples for usewith thick tissue and short staples for use with thin tissue. In somecircumstances, however, the tissue being stapled did not have aconsistent thickness and, thus, some staples were unable to achieve thedesired fired configuration. For example, FIG. 250 illustrates a tallstaple used in thin tissue. Referring now to FIG. 251, when a tissuethickness compensator, such as tissue thickness compensator 10020, forexample, is used with thin tissue, for example, the larger staple may beformed to a desired fired configuration.

Owing to the compressibility of the tissue thickness compensator, thetissue thickness compensator can compensate for the thickness of thetissue captured within each staple. More particularly, referring now toFIGS. 245 and 246, a tissue thickness compensator, such as tissuethickness compensator 10020, for example, can consume larger and/orsmaller portions of the staple entrapment area 10039 of each staple10030 depending on the thickness and/or type of tissue contained withinthe staple entrapment area 10039. For example, if thinner tissue T iscaptured within a staple 10030, the tissue thickness compensator 10020can consume a larger portion of the staple entrapment area 10039 ascompared to circumstances where thicker tissue T is captured within thestaple 10030. Correspondingly, if thicker tissue T is captured within astaple 10030, the tissue thickness compensator 10020 can consume asmaller portion of the staple entrapment area 10039 as compared to thecircumstances where thinner tissue T is captured within the staple10030. In this way, the tissue thickness compensator can compensate forthinner tissue and/or thicker tissue and assure that a compressivepressure is applied to the tissue irrespective, or at leastsubstantially irrespective, of the tissue thickness captured within thestaples. In addition to the above, the tissue thickness compensator10020 can compensate for different types, or compressibilities, oftissues captured within different staples 10030. Referring now to FIG.246, the tissue thickness compensator 10020 can apply a compressiveforce to vascular tissue T which can include vessels V and, as a result,restrict the flow of blood through the less compressible vessels V whilestill applying a desired compressive pressure to the surrounding tissueT. In various circumstances, further to the above, the tissue thicknesscompensator 10020 can also compensate for malformed staples. Referringto FIG. 247, the malformation of various staples 10030 can result inlarger staple entrapment areas 10039 being defined within such staples.Owing to the resiliency of the tissue thickness compensator 10020,referring now to FIG. 248, the tissue thickness compensator 10020positioned within malformed staples 10030 may still apply a sufficientcompressive pressure to the tissue T eventhough the staple entrapmentareas 10039 defined within such malformed staples 10030 may be enlarged.In various circumstances, the tissue thickness compensator 10020 locatedintermediate adjacent staples 10030 can be biased against the tissue Tby properly-formed staples 10030 surrounding a malformed staple 10030and, as a result, apply a compressive pressure to the tissue surroundingand/or captured within the malformed staple 10030, for example. Invarious circumstances, a tissue thickness compensator can compensate fordifferent tissue densities which can arise due to calcifications,fibrous areas, and/or tissue that has been previously stapled ortreated, for example.

In various embodiments, a fixed, or unchangeable, tissue gap can bedefined between the support portion and the anvil and, as a result, thestaples may be deformed to a predetermined height regardless of thethickness of the tissue captured within the staples. When a tissuethickness compensator is used with these embodiments, the tissuethickness compensator can adapt to the tissue captured between the anviland the support portion staple cartridge and, owing to the resiliency ofthe tissue thickness compensator, the tissue thickness compensator canapply an additional compressive pressure to the tissue. Referring now toFIGS. 252-257, a staple 10030 has been formed to a predefined height H.With regard to FIG. 252, a tissue thickness compensator has not beenutilized and the tissue T consumes the entirety of the staple entrapmentarea 10039. With regard to FIG. 259, a portion of a tissue thicknesscompensator 10020 has been captured within the staple 10030, compressedthe tissue T, and consumed at least a portion of the staple entrapmentarea 10039. Referring now to FIG. 254, thin tissue T has been capturedwithin the staple 10030. In this embodiment, the compressed tissue T hasa height of approximately 2/9H and the compressed tissue thicknesscompensator 10020 has a height of approximately 7/9H, for example.Referring now to FIG. 255, tissue T having an intermediate thickness hasbeen captured within the staple 10030. In this embodiment, thecompressed tissue T has a height of approximately 4/9H and thecompressed tissue thickness compensator 10020 has a height ofapproximately 5/9H, for example. Referring now to FIG. 256, tissue Thaving an intermediate thickness has been captured within the staple10030. In this embodiment, the compressed tissue T has a height ofapproximately ⅔H and the compressed tissue thickness compensator 10020has a height of approximately ⅓H, for example. Referring now to FIG.255, thick tissue T has been captured within the staple 10030. In thisembodiment, the compressed tissue T has a height of approximately 8/9Hand the compressed tissue thickness compensator 10020 has a height ofapproximately 1/9H, for example. In various circumstances, the tissuethickness compensator can comprise a compressed height which comprisesapproximately 10% of the staple entrapment height, approximately 20% ofthe staple entrapment height, approximately 30% of the staple entrapmentheight, approximately 40% of the staple entrapment height, approximately50% of the staple entrapment height, approximately 60% of the stapleentrapment height, approximately 70% of the staple entrapment height,approximately 80% of the staple entrapment height, and/or approximately90% of the staple entrapment height, for example.

In various embodiments, the staples 10030 can comprise any suitableunformed height. In certain embodiments, the staples 10030 can comprisean unformed height between approximately 2 mm and approximately 4.8 mm,for example. The staples 10030 can comprise an unformed height ofapproximately 2.0 mm, approximately 2.5 mm, approximately 3.0 mm,approximately 3.4 mm, approximately 3.5 mm, approximately 3.8 mm,approximately 4.0 mm, approximately 4.1 mm, and/or approximately 4.8 mm,for example. In various embodiments, the height H to which the staplescan be deformed can be dictated by the distance between the deck surface10011 of the support portion 10010 and the opposing anvil. In at leastone embodiment, the distance between the deck surface 10011 and thetissue-contacting surface of the anvil can be approximately 0.097″, forexample. The height H can also be dictated by the depth of the formingpockets defined within the anvil. In at least one embodiment, theforming pockets can have a depth measured from the tissue-contactingsurface, for example. In various embodiments, as described in greaterdetail below, the staple cartridge 10000 can further comprise stapledrivers which can lift the staples 10030 toward the anvil and, in atleast one embodiment, lift, or “overdrive”, the staples above the decksurface 10011. In such embodiments, the height H to which the staples10030 are formed can also be dictated by the distance in which thestaples 10030 are overdriven. In at least one such embodiment, thestaples 10030 can be overdriven by approximately 0.028″, for example,and can result in the staples 10030 being formed to a height ofapproximately 0.189″, for example. In various embodiments, the staples10030 can be formed to a height of approximately 0.8 mm, approximately1.0 mm, approximately 1.5 mm, approximately 1.8 mm, approximately 2.0mm, and/or approximately 2.25 mm, for example. In certain embodiments,the staples can be formed to a height between approximately 2.25 mm andapproximately 3.0 mm, for example. Further to the above, the height ofthe staple entrapment area of a staple can be determined by the formedheight of the staple and the width, or diameter, of the wire comprisingthe staple. In various embodiments, the height of the staple entrapmentarea 10039 of a staple 10030 can comprise the formed height H of thestaple less two diameter widths of the wire. In certain embodiments, thestaple wire can comprise a diameter of approximately 0.0089″, forexample. In various embodiments, the staple wire can comprise a diameterbetween approximately 0.0069″ and approximately 0.0119″, for example. Inat least one exemplary embodiment, the formed height H of a staple 10030can be approximately 0.189″ and the staple wire diameter can beapproximately 0.0089″ resulting in a staple entrapment height ofapproximately 0.171″, for example.

In various embodiments, further to the above, the tissue thicknesscompensator can comprise an uncompressed, or pre-deployed, height andcan be configured to deform to one of a plurality of compressed heights.In certain embodiments, the tissue thickness compensator can comprise anuncompressed height of approximately 0.125″, for example. In variousembodiments, the tissue thickness compensator can comprise anuncompressed height of greater than or equal to approximately 0.080″,for example. In at least one embodiment, the tissue thicknesscompensator can comprise an uncompressed, or pre-deployed, height whichis greater than the unfired height of the staples. In at least oneembodiment, the uncompressed, or pre-deployed, height of the tissuethickness compensator can be approximately 10% taller, approximately 20%taller, approximately 30% taller, approximately 40% taller,approximately 50% taller, approximately 60% taller, approximately 70%taller, approximately 80% taller, approximately 90% taller, and/orapproximately 100% taller than the unfired height of the staples, forexample. In at least one embodiment, the uncompressed, or pre-deployed,height of the tissue thickness compensator can be up to approximately100% taller than the unfired height of the staples, for example. Incertain embodiments, the uncompressed, or pre-deployed, height of thetissue thickness compensator can be over 100% taller than the unfiredheight of the staples, for example. In at least one embodiment, thetissue thickness compensator can comprise an uncompressed height whichis equal to the unfired height of the staples. In at least oneembodiment, the tissue thickness compensator can comprise anuncompressed height which is less than the unfired height of thestaples. In at least one embodiment, the uncompressed, or pre-deployed,height of the thickness compensator can be approximately 10% shorter,approximately 20% shorter, approximately 30% shorter, approximately 40%shorter, approximately 50% shorter, approximately 60% shorter,approximately 70% shorter, approximately 80% shorter, and/orapproximately 90% shorter than the unfired height of the staples, forexample. In various embodiments, the compressible second portion cancomprise an uncompressed height which is taller than an uncompressedheight of the tissue T being stapled. In certain embodiments, the tissuethickness compensator can comprise an uncompressed height which is equalto an uncompressed height of the tissue T being stapled. In variousembodiments, the tissue thickness compensator can comprise anuncompressed height which is shorter than an uncompressed height of thetissue T being stapled.

As described above, a tissue thickness compensator can be compressedwithin a plurality of formed staples regardless of whether thick tissueor thin tissue is captured within the staples. In at least one exemplaryembodiment, the staples within a staple line, or row, can be deformedsuch that the staple entrapment area of each staple comprises a heightof approximately 2.0 mm, for example, wherein the tissue T and thetissue thickness compensator can be compressed within this height. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.75 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.25 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.50 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.50 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.25 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.75 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.0 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately1.0 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 0.75 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately1.25 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.50 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.50 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 0.25 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately1.75 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example.

In various embodiments, further to the above, the tissue thicknesscompensator can comprise an uncompressed height which is less than thefired height of the staples. In certain embodiments, the tissuethickness compensator can comprise an uncompressed height which is equalto the fired height of the staples. In certain other embodiments, thetissue thickness compensator can comprise an uncompressed height whichis taller than the fired height of the staples. In at least one suchembodiment, the uncompressed height of a tissue thickness compensatorcan comprise a thickness which is approximately 110% of the formedstaple height, approximately 120% of the formed staple height,approximately 130% of the formed staple height, approximately 140% ofthe formed staple height, approximately 150% of the formed stapleheight, approximately 160% of the formed staple height, approximately170% of the formed staple height, approximately 180% of the formedstaple height, approximately 190% of the formed staple height, and/orapproximately 200% of the formed staple height, for example. In certainembodiments, the tissue thickness compensator can comprise anuncompressed height which is more than twice the fired height of thestaples. In various embodiments, the tissue thickness compensator cancomprise a compressed height which is from approximately 85% toapproximately 150% of the formed staple height, for example. In variousembodiments, as described above, the tissue thickness compensator can becompressed between an uncompressed thickness and a compressed thickness.In certain embodiments, the compressed thickness of a tissue thicknesscompensator can be approximately 10% of its uncompressed thickness,approximately 20% of its uncompressed thickness, approximately 30% ofits uncompressed thickness, approximately 40% of its uncompressedthickness, approximately 50% of its uncompressed thickness,approximately 60% of its uncompressed thickness, approximately 70% ofits uncompressed thickness, approximately 80% of its uncompressedthickness, and/or approximately 90% of its uncompressed thickness, forexample. In various embodiments, the uncompressed thickness of thetissue thickness compensator can be approximately two times,approximately ten times, approximately fifty times, and/or approximatelyone hundred times thicker than its compressed thickness, for example. Inat least one embodiment, the compressed thickness of the tissuethickness compensator can be between approximately 60% and approximately99% of its uncompressed thickness. In at least one embodiment, theuncompressed thickness of the tissue thickness compensator can be atleast 50% thicker than its compressed thickness. In at least oneembodiment, the uncompressed thickness of the tissue thicknesscompensator can be up to one hundred times thicker than its compressedthickness. In various embodiments, the compressible second portion canbe elastic, or at least partially elastic, and can bias the tissue Tagainst the deformed legs of the staples. In at least one suchembodiment, the compressible second portion can resiliently expandbetween the tissue T and the base of the staple in order to push thetissue T against the legs of the staple. In certain embodiments,discussed in further detail below, the tissue thickness compensator canbe positioned intermediate the tissue T and the deformed staple legs. Invarious circumstances, as a result of the above, the tissue thicknesscompensator can be configured to consume any gaps within the stapleentrapment area.

In various embodiments, the tissue thickness compensator may comprise apolymeric composition. The polymeric composition may comprise one ormore synthetic polymer and/or one or more non-synthetic polymer. Thesynthetic polymer may comprise a synthetic absorbable polymer and/or asynthetic non-absorbable polymer. In various embodiments, the polymericcomposition may comprise a biocompatible foam, for example. Thebiocompatible foam may comprise a porous, open cell foam and/or aporous, closed cell foam, for example. The biocompatible foam can have auniform pore morphology or may have a gradient pore morphology (i.e.small pores gradually increasing in size to large pores across thethickness of the foam in one direction). In various embodiments, thepolymeric composition may comprise one or more of a porous scaffold, aporous matrix, a gel matrix, a hydrogel matrix, a solution matrix, afilamentous matrix, a tubular matrix, a composite matrix, a membranousmatrix, a biostable polymer, and a biodegradable polymer, andcombinations thereof. For example, the tissue thickness compensator maycomprise a foam reinforced by a filamentous matrix or may comprise afoam having an additional hydrogel layer that expands in the presence ofbodily fluids to further provide the compression on the tissue. Invarious embodiments, a tissue thickness compensator could also becomprised of a coating on a material and/or a second or third layer thatexpands in the presence of bodily fluids to further provide thecompression on the tissue. Such a layer could be a hydrogel that couldbe a synthetic and/or naturally derived material and could be eitherbiodurable and/or biodegradable, for example. In certain embodiments, atissue thickness compensator could be reinforced with fibrous non-wovenmaterials or fibrous mesh type elements, for example, that can provideadditional flexibility, stiffness, and/or strength. In variousembodiments, a tissue thickness compensator that has a porous morphologywhich exhibits a gradient structure such as, for example, small pores onone surface and larger pores on the other surface. Such morphology couldbe more optimal for tissue in-growth or hemostatic behavior. Further,the gradient could be also compositional with a varying bio-absorptionprofile. A short term absorption profile may be preferred to addresshemostasis while a long term absorption profile may address bettertissue healing without leakages.

Examples of non-synthetic polymers include, but are not limited to,lypholized polysaccharide, glycoprotein, elastin, proteoglycan, gelatin,collagen, and oxidized regenerated cellulose (ORC). Examples ofsynthetic absorbable polymers include, but are not limited to,poly(lactic acid) (PLA), poly(L-lactic acid) (PLLA), polycaprolactone(PCL), polyglycolic acid (PGA), poly(trimethylene carbonate) (TMC),polyethylene terephthalate (PET), polyhydroxyalkanoate (PHA), acopolymer of glycolide and ε-caprolactone (PGCL), a copolymer ofglycolide and -trimethylene carbonate, poly(glycerol sebacate) (PGS),polydioxanone, poly(orthoesters), polyanhydrides, polysaccharides,poly(ester-amides), tyrosine-based polyarylates, tyrosine-basedpolyiminocarbonates, tyrosine-based polycarbonates,poly(D,L-lactide-urethane), poly(B-hydroxybutyrate),poly(ε-caprolactone), polyethyleneglycol (PEG),poly[bis(carboxylatophenoxy)phosphazene], poly(amino acids),pseudo-poly(amino acids), absorbable polyurethanes, and combinationsthereof. In various embodiments, the polymeric composition may comprisefrom approximately 50% to approximately 90% by weight of the polymericcomposition of PLLA and approximately 50% to approximately 10% by weightof the polymeric composition of PCL, for example. In at least oneembodiment, the polymeric composition may comprise approximately 70% byweight of PLLA and approximately 30% by weight of PCL, for example. Invarious embodiments, the polymeric composition may comprise fromapproximately 55% to approximately 85% by weight of the polymericcomposition of PGA and 15% to 45% by weight of the polymeric compositionof PCL, for example. In at least one embodiment, the polymericcomposition may comprise approximately 65% by weight of PGA andapproximately 35% by weight of PCL, for example. In various embodiments,the polymeric composition may comprise from approximately 90% toapproximately 95% by weight of the polymeric composition of PGA andapproximately 5% to approximately 10% by weight of the polymericcomposition of PLA, for example.

In various embodiments, the synthetic absorbable polymer may comprise abioabsorbable, biocompatible elastomeric copolymer. Suitablebioabsorbable, biocompatible elastomeric copolymers include but are notlimited to copolymers of epsilon-caprolactone and glycolide (preferablyhaving a mole ratio of epsilon-caprolactone to glycolide of from about30:70 to about 70:30, preferably 35:65 to about 65:35, and morepreferably 45:55 to 35:65); elastomeric copolymers ofepsilon-caprolactone and lactide, including L-lactide, D-lactide blendsthereof or lactic acid copolymers (preferably having a mole ratio ofepsilon-caprolactone to lactide of from about 35:65 to about 65:35 andmore preferably 45:55 to 30:70) elastomeric copolymers of p-dioxanone(1,4-dioxan-2-one) and lactide including L-lactide, D-lactide and lacticacid (preferably having a mole ratio of p-dioxanone to lactide of fromabout 40:60 to about 60:40); elastomeric copolymers ofepsilon-caprolactone and p-dioxanone (preferably having a mole ratio ofepsilon-caprolactone to p-dioxanone of from about 30:70 to about 70:30);elastomeric copolymers of p-dioxanone and trimethylene carbonate(preferably having a mole ratio of p-dioxanone to trimethylene carbonateof from about 30:70 to about 70:30); elastomeric copolymers oftrimethylene carbonate and glycolide (preferably having a mole ratio oftrimethylene carbonate to glycolide of from about 30:70 to about 70:30);elastomeric copolymer of trimethylene carbonate and lactide includingL-lactide, D-lactide, blends thereof or lactic acid copolymers(preferably having a mole ratio of trimethylene carbonate to lactide offrom about 30:70 to about 70:30) and blends thereof. In one embodiment,the elastomeric copolymer is a copolymer of glycolide andepsilon-caprolactone. In another embodiment, the elastomeric copolymeris a copolymer of lactide and epsilon-caprolactone.

The disclosures of U.S. Pat. No. 5,468,253, entitled ELASTOMERIC MEDICALDEVICE, which issued on Nov. 21, 1995, and U.S. Pat. No. 6,325,810,entitled FOAM BUTTRESS FOR STAPLING APPARATUS, which issued on Dec. 4,2001, are hereby incorporated by reference in their respectiveentireties.

In various embodiments, the synthetic absorbable polymer may compriseone or more of 90/10 poly(glycolide-L-lactide) copolymer, commerciallyavailable from Ethicon, Inc. under the trade designation VICRYL(polyglactic 910), polyglycolide, commercially available from AmericanCyanamid Co. under the trade designation DEXON, polydioxanone,commercially available from Ethicon, Inc. under the trade designationPDS, poly(glycolide-trimethylene carbonate) random block copolymer,commercially available from American Cyanamid Co. under the tradedesignation MAXON, 75/25poly(glycolide-ε-caprolactone-poliglecaprolactone 25) copolymer,commercially available from Ethicon under the trade designationMONOCRYL, for example.

Examples of synthetic non-absorbable polymers include, but are notlimited to, foamed polyurethane, polypropylene (PP), polyethylene (PE),polycarbonate, polyamides, such as nylon, polyvinylchloride (PVC),polymethylmetacrylate (PMMA), polystyrene (PS), polyester,polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE),polytrifluorochloroethylene (PTFCE), polyvinylfluoride (PVF),fluorinated ethylene propylene (FEP), polyacetal, polysulfone, andcombinations thereof. The synthetic non-absorbable polymers may include,but are not limited to, foamed elastomers and porous elastomers, suchas, for example, silicone, polyisoprene, and rubber. In variousembodiments, the synthetic polymers may comprise expandedpolytetrafluoroethylene (ePTFE), commercially available from W. L. Gore& Associates, Inc. under the trade designation GORE-TEX Soft TissuePatch and co-polyetherester urethane foam commercially available fromPolyganics under the trade designation NASOPORE.

The polymeric composition of a tissue thickness compensator may becharacterized by percent porosity, pore size, and/or hardness, forexample. In various embodiments, the polymeric composition may have apercent porosity from approximately 30% by volume to approximately 99%by volume, for example. In certain embodiments, the polymericcomposition may have a percent porosity from approximately 60% by volumeto approximately 98% by volume, for example. In various embodiments, thepolymeric composition may have a percent porosity from approximately 85%by volume to approximately 97% by volume, for example. In at least oneembodiment, the polymeric composition may comprise approximately 70% byweight of PLLA and approximately 30% by weight of PCL, for example, andcan comprise approximately 90% porosity by volume, for example. In atleast one such embodiment, as a result, the polymeric composition wouldcomprise approximately 10% copolymer by volume. In at least oneembodiment, the polymeric composition may comprise approximately 65% byweight of PGA and approximately 35% by weight of PCL, for example, andcan have a percent porosity from approximately 93% by volume toapproximately 95% by volume, for example. In various embodiments, thepolymeric composition may comprise a greater than 85% porosity byvolume. The polymeric composition may have a pore size fromapproximately 5 micrometers to approximately 2000 micrometers, forexample. In various embodiments, the polymeric composition may have apore size between approximately 10 micrometers to approximately 100micrometers, for example. In at least one such embodiment, the polymericcomposition can comprise a copolymer of PGA and PCL, for example. Incertain embodiments, the polymeric composition may have a pore sizebetween approximately 100 micrometers to approximately 1000 micrometers,for example. In at least one such embodiment, the polymeric compositioncan comprise a copolymer of PLLA and PCL, for example. According tocertain aspects, the hardness of a polymeric composition may beexpressed in terms of the Shore Hardness, which can defined as theresistance to permanent indentation of a material as determined with adurometer, such as a Shore Durometer. In order to assess the durometervalue for a given material, a pressure is applied to the material with adurometer indenter foot in accordance with ASTM procedure D2240-00,entitled, “Standard Test Method for Rubber Property-Durometer Hardness”,the entirety of which is incorporated herein by reference. The durometerindenter foot may be applied to the material for a sufficient period oftime, such as 15 seconds, for example, wherein a reading is then takenfrom the appropriate scale. Depending on the type of scale being used, areading of 0 can be obtained when the indenter foot completelypenetrates the material, and a reading of 100 can be obtained when nopenetration into the material occurs. This reading is dimensionless. Invarious embodiments, the durometer may be determined in accordance withany suitable scale, such as Type A and/or Type OO scales, for example,in accordance with ASTM D2240-00. In various embodiments, the polymericcomposition of a tissue thickness compensator may have a Shore Ahardness value from approximately 4 A to approximately 16 A, forexample, which is approximately 45 OO to approximately 65 OO on theShore OO range. In at least one such embodiment, the polymericcomposition can comprise a PLLA/PCL copolymer or a PGA/PCL copolymer,for example. In various embodiments, the polymeric composition of atissue thickness compensator may have a Shore A Hardness value of lessthan 15 A. In various embodiments, the polymeric composition of a tissuethickness compensator may have a Shore A Hardness value of less than 10A. In various embodiments, the polymeric composition of a tissuethickness compensator may have a Shore A Hardness value of less than 5A. In certain embodiments, the polymeric material may have a Shore OOcomposition value from approximately 35 OO to approximately 75 OO, forexample.

In various embodiments, the polymeric composition may have at least twoof the above-identified properties. In various embodiments, thepolymeric composition may have at least three of the above-identifiedproperties. The polymeric composition may have a porosity from 85% to97% by volume, a pore size from 5 micrometers to 2000 micrometers, and aShore A hardness value from 4 A to 16 A and Shore OO hardness value from45 OO to 65 OO, for example. In at least one embodiment, the polymericcomposition may comprise 70% by weight of the polymeric composition ofPLLA and 30% by weight of the polymeric composition of PCL having aporosity of 90% by volume, a pore size from 100 micrometers to 1000micrometers, and a Shore A hardness value from 4 A to 16 A and Shore OOhardness value from 45 OO to 65 OO, for example. In at least oneembodiment, the polymeric composition may comprise 65% by weight of thepolymeric composition of PGA and 35% by weight of the polymericcomposition of PCL having a porosity from 93% to 95% by volume, a poresize from 10 micrometers to 100 micrometers, and a Shore A hardnessvalue from 4 A to 16 A and Shore OO hardness value from 45 OO to 65 OO,for example.

In various embodiments, the polymeric composition may comprise apharmaceutically active agent. The polymeric composition may release atherapeutically effective amount of the pharmaceutically active agent.In various embodiments, the pharmaceutically active agent may bereleased as the polymeric composition is desorbed/absorbed. In variousembodiments, the pharmaceutically active agent may be released intofluid, such as, for example, blood, passing over or through thepolymeric composition. Examples of pharmaceutically active agents mayinclude, but are not limited to, hemostatic agents and drugs, such as,for example, fibrin, thrombin, and oxidized regenerated cellulose (ORC);anti-inflammatory drugs, such as, for example, diclofenac, aspirin,naproxen, sulindac, and hydrocortisone; antibiotic and antimicrobialdrug or agents, such as, for example, triclosan, ionic silver,ampicillin, gentamicin, polymyxin B, chloramphenicol; and anticanceragents, such as, for example, cisplatin, mitomycin, adriamycin.

In various embodiments, referring now to FIG. 216, a staple cartridge,such as staple cartridge 10000, for example, can comprise a supportportion 10010 and a compressible tissue thickness compensator 10020.Referring now to FIGS. 218-220, the support portion 10010 can comprise adeck surface 10011 and a plurality of staple cavities 10012 definedwithin the support portion 10010. Each staple cavity 10012 can be sizedand configured to removably store a staple, such as a staple 10030, forexample, therein. The staple cartridge 10000 can further comprise aplurality of staple drivers 10040 which can each be configured tosupport one or more staples 10030 within the staple cavities 10012 whenthe staples 10030 and the staple drivers 10040 are in their unfiredpositions. In at least one such embodiment, referring primarily to FIGS.224 and 225, each staple driver 10040 can comprise one or more cradles,or troughs, 10041, for example, which can be configured to support thestaples and limit relative movement between the staples 10030 and thestaple drivers 10040. In various embodiments, referring again to FIG.218, the staple cartridge 10000 can further comprise a staple-firingsled 10050 which can be moved from a proximal end 10001 to a distal end10002 of the staple cartridge in order to sequentially lift the stapledrivers 10040 and the staples 10030 from their unfired positions towardan anvil positioned opposite the staple cartridge 10000. In certainembodiments, referring primarily to FIGS. 218 and 220, each staple 10030can comprise a base 10031 and one or more legs 10032 extending from thebase 10031 wherein each staple can be at least one of substantiallyU-shaped and substantially V-shaped, for example. In at least oneembodiment, the staples 10030 can be configured such that the tips ofthe staple legs 10032 are recessed with respect to the deck surface10011 of the support portion 10010 when the staples 10030 are in theirunfired positions. In at least one embodiment, the staples 10030 can beconfigured such that the tips of the staple legs 10032 are flush withrespect to the deck surface 10011 of the support portion 10010 when thestaples 10030 are in their unfired positions. In at least oneembodiment, the staples 10030 can be configured such that the tips ofthe staple legs 10032, or at least some portion of the staple legs10032, extend above the deck surface 10011 of the support portion 10010when the staples 10030 are in their unfired positions. In suchembodiments, the staple legs 10032 can extend into and can be embeddedwithin the tissue thickness compensator 10020 when the staples 10030 arein their unfired positions. In at least one such embodiment, the staplelegs 10032 can extend above the deck surface 10011 by approximately0.075″, for example. In various embodiments, the staple legs 10032 canextend above the deck surface 10011 by a distance between approximately0.025″ and approximately 0.125″, for example. In certain embodiments,further to the above, the tissue thickness compensator 10020 cancomprise an uncompressed thickness between approximately 0.08″ andapproximately 0.125″, for example.

In use, further to the above and referring primarily to FIG. 233, ananvil, such as anvil, 10060, for example, can be moved into a closedposition opposite the staple cartridge 10000. As described in greaterdetail below, the anvil 10060 can position tissue against the tissuethickness compensator 10020 and, in various embodiments, compress thetissue thickness compensator 10020 against the deck surface 10011 of thesupport portion 10010, for example. Once the anvil 10060 has beensuitably positioned, the staples 10030 can be deployed, as alsoillustrated in FIG. 233. In various embodiments, as mentioned above, thestaple-firing sled 10050 can be moved from the proximal end 10001 of thestaple cartridge 10000 toward the distal end 10002, as illustrated inFIG. 234. As the sled 10050 is advanced, the sled 10050 can contact thestaple drivers 10040 and lift the staple drivers 10040 upwardly withinthe staple cavities 10012. In at least one embodiment, the sled 10050and the staple drivers 10040 can each comprise one or more ramps, orinclined surfaces, which can co-operate to move the staple drivers 10040upwardly from their unfired positions. In at least one such embodiment,referring to FIGS. 221-225, each staple driver 10040 can comprise atleast one inclined surface 10042 and the sled 10050 can comprise one ormore inclined surfaces 10052 which can be configured such that theinclined surfaces 10052 can slide under the inclined surface 10042 asthe sled 10050 is advanced distally within the staple cartridge. As thestaple drivers 10040 are lifted upwardly within their respective staplecavities 10012, the staple drivers 10040 can lift the staples 10030upwardly such that the staples 10030 can emerge from their staplecavities 10012 through openings in the staple deck 10011. During anexemplary firing sequence, referring primarily to FIGS. 227-229, thesled 10050 can first contact staple 10030 a and begin to lift the staple10030 a upwardly. As the sled 10050 is advanced further distally, thesled 10050 can begin to lift staples 10030 b, 10030 c, 10030 d, 10030 e,and 10030 f, and any other subsequent staples, in a sequential order. Asillustrated in FIG. 229, the sled 10050 can drive the staples 10030upwardly such that the legs 10032 of the staples contact the opposinganvil, are deformed to a desired shape, and ejected therefrom thesupport portion 10010. In various circumstances, the sled 10030 can moveseveral staples upwardly at the same time as part of a firing sequence.With regard to the firing sequence illustrated in FIG. 229, the staples10030 a and 10030 b have been moved into their fully fired positions andejected from the support portion 10010, the staples 10030 c and 10030 dare in the process of being fired and are at least partially containedwithin the support portion 10010, and the staples 10030 e and 10030 fare still in their unfired positions.

As discussed above, and referring to FIG. 235, the staple legs 10032 ofthe staples 10030 can extend above the deck surface 10011 of the supportportion 10010 when the staples 10030 are in their unfired positions.With further regard to this firing sequence illustrated in FIG. 229, thestaples 10030 e and 10030 f are illustrated in their unfired positionand their staple legs 10032 extend above the deck surface 10011 and intothe tissue thickness compensator 10020. In various embodiments, the tipsof the staple legs 10032, or any other portion of the staple legs 10032,may not protrude through a top tissue-contacting surface 10021 of thetissue thickness compensator 10020 when the staples 10030 are in theirunfired positions. As the staples 10030 are moved from their unfiredpositions to their fired positions, as illustrated in FIG. 229, the tipsof the staple legs can protrude through the tissue-contacting surface10032. In various embodiments, the tips of the staple legs 10032 cancomprise sharp tips which can incise and penetrate the tissue thicknesscompensator 10020. In certain embodiments, the tissue thicknesscompensator 10020 can comprise a plurality of apertures which can beconfigured to receive the staple legs 10032 and allow the staple legs10032 to slide relative to the tissue thickness compensator 10020. Incertain embodiments, the support portion 10010 can further comprise aplurality of guides 10013 extending from the deck surface 10011. Theguides 10013 can be positioned adjacent to the staple cavity openings inthe deck surface 10011 such that the staple legs 10032 can be at leastpartially supported by the guides 10013. In certain embodiments, a guide10013 can be positioned at a proximal end and/or a distal end of astaple cavity opening. In various embodiments, a first guide 10013 canbe positioned at a first end of each staple cavity opening and a secondguide 10013 can be positioned at a second end of each staple cavityopening such that each first guide 10013 can support a first staple leg10032 of a staple 10030 and each second guide 10013 can support a secondstaple leg 10032 of the staple. In at least one embodiment, referring toFIG. 235, each guide 10013 can comprise a groove or slot, such as groove10016, for example, within which a staple leg 10032 can be slidablyreceived. In various embodiments, each guide 10013 can comprise a cleat,protrusion, and/or spike that can extend from the deck surface 10011 andcan extend into the tissue thickness compensator 10020. In at least oneembodiment, as discussed in greater detail below, the cleats,protrusions, and/or spikes can reduce relative movement between thetissue thickness compensator 10020 and the support portion 10010. Incertain embodiments, the tips of the staple legs 10032 may be positionedwithin the guides 10013 and may not extend above the top surfaces of theguides 10013 when the staples 10030 are in their unfired position. In atleast such embodiment, the guides 10013 can define a guide height andthe staples 10030 may not extend above this guide height when they arein their unfired position.

In various embodiments, a tissue thickness compensator, such as tissuethickness compensator 10020, for example, can be comprised of a singlesheet of material. In at least one embodiment, a tissue thicknesscompensator can comprise a continuous sheet of material which can coverthe entire top deck surface 10011 of the support portion 10010 or,alternatively, cover less than the entire deck surface 10011. In certainembodiments, the sheet of material can cover the staple cavity openingsin the support portion 10010 while, in other embodiments, the sheet ofmaterial can comprise openings which can be aligned, or at leastpartially aligned, with the staple cavity openings. In variousembodiments, a tissue thickness compensator can be comprised of multiplelayers of material. In some embodiments, referring now to FIG. 217, atissue thickness compensator can comprise a compressible core and a wrapsurrounding the compressible core. In certain embodiments, a wrap 10022can be configured to releasably hold the compressible core to thesupport portion 10010. In at least one such embodiment, the supportportion 10010 can comprise one or more projections, such as projections10014 (FIG. 220), for example, extending therefrom which can be receivedwithin one or more apertures and/or slots, such as apertures 10024, forexample, defined in the wrap 10022. The projections 10014 and theapertures 10024 can be configured such that the projections 10014 canretain the wrap 10022 to the support portion 10010. In at least oneembodiment, the ends of the projections 10014 can be deformed, such asby a heat-stake process, for example, in order to enlarge the ends ofthe projections 10014 and, as a result, limit the relative movementbetween the wrap 10022 and the support portion 10010. In at least oneembodiment, the wrap 10022 can comprise one or more perforations 10025which can facilitate the release of the wrap 10022 from the supportportion 10010, as illustrated in FIG. 217. Referring now to FIG. 226, atissue thickness compensator can comprise a wrap 10222 including aplurality of apertures 10223, wherein the apertures 10223 can bealigned, or at least partially aligned, with the staple cavity openingsin the support portion 10010. In certain embodiments, the core of thetissue thickness compensator can also comprise apertures which arealigned, or at least partially aligned, with the apertures 10223 in thewrap 10222. In other embodiments, the core of the tissue thicknesscompensator can comprise a continuous body and can extend underneath theapertures 10223 such that the continuous body covers the staple cavityopenings in the deck surface 10011.

In various embodiments, as described above, a tissue thicknesscompensator can comprise a wrap for releasably holding a compressiblecore to the support portion 10010. In at least one such embodiment,referring to FIG. 218, a staple cartridge can further comprise retainerclips 10026 which can be configured to inhibit the wrap, and thecompressible core, from prematurely detaching from the support portion10010. In various embodiments, each retainer clip 10026 can compriseapertures 10028 which can be configured to receive the projections 10014extending from the support portion 10010 such that the retainer clips10026 can be retained to the support portion 10010. In certainembodiments, the retainer clips 10026 can each comprise at least one panportion 10027 which can extend underneath the support portion 10010 andcan support and retain the staple drivers 10040 within the supportportion 10010. In certain embodiments, as described above, a tissuethickness compensator can be removably attached to the support portion10010 by the staples 10030. More particularly, as also described above,the legs of the staples 10030 can extend into the tissue thicknesscompensator 10020 when the staples 10030 are in their unfired positionand, as a result, releasably hold the tissue thickness compensator 10020to the support portion 10010. In at least one embodiment, the legs ofthe staples 10030 can be in contact with the sidewalls of theirrespective staple cavities 10012 wherein, owing to friction between thestaple legs 10032 and the sidewalls, the staples 10030 and the tissuethickness compensator 10020 can be retained in position until thestaples 10030 are deployed from the staple cartridge 10000. When thestaples 10030 are deployed, the tissue thickness compensator 10020 canbe captured within the staples 10030 and held against the stapled tissueT. When the anvil is thereafter moved into an open position to releasethe tissue T, the support portion 10010 can be moved away from thetissue thickness compensator 10020 which has been fastened to thetissue. In certain embodiments, an adhesive can be utilized to removablyhold the tissue thickness compensator 10020 to the support portion10010. In at least one embodiment, a two-part adhesive can be utilizedwherein, in at least one embodiment, a first part of the adhesive can beplaced on the deck surface 10011 and a second part of the adhesive canbe placed on the tissue thickness compensator 10020 such that, when thetissue thickness compensator 10020 is placed against the deck surface10011, the first part can contact the second part to active the adhesiveand detachably bond the tissue thickness compensator 10020 to thesupport portion 10010. In various embodiments, any other suitable meanscould be used to detachably retain the tissue thickness compensator tothe support portion of a staple cartridge.

In various embodiments, further to the above, the sled 10050 can beadvanced from the proximal end 10001 to the distal end 10002 to fullydeploy all of the staples 10030 contained within the staple cartridge10000. In at least one embodiment, referring now to FIGS. 258-262, thesled 10050 can be advanced distally within a longitudinal cavity 10016within the support portion 10010 by a firing member, or knife bar, 10052of a surgical stapler. In use, the staple cartridge 10000 can beinserted into a staple cartridge channel in a jaw of the surgicalstapler, such as staple cartridge channel 10070, for example, and thefiring member 10052 can be advanced into contact with the sled 10050, asillustrated in FIG. 258. As the sled 10050 is advanced distally by thefiring member 10052, the sled 10050 can contact the proximal-most stapledriver, or drivers, 10040 and fire, or eject, the staples 10030 from thecartridge body 10010, as described above. As illustrated in FIG. 258,the firing member 10052 can further comprise a cutting edge 10053 whichcan be advanced distally through a knife slot in the support portion10010 as the staples 10030 are being fired. In various embodiments, acorresponding knife slot can extend through the anvil positionedopposite the staple cartridge 10000 such that, in at least oneembodiment, the cutting edge 10053 can extend between the anvil and thesupport portion 10010 and incise the tissue and the tissue thicknesscompensator positioned therebetween. In various circumstances, the sled10050 can be advanced distally by the firing member 10052 until the sled10050 reaches the distal end 10002 of the staple cartridge 10000, asillustrated in FIG. 260. At such point, the firing member 10052 can beretracted proximally. In some embodiments, the sled 10050 can beretracted proximally with the firing member 10052 but, in variousembodiments, referring now to FIG. 261, the sled 10050 can be leftbehind in the distal end 10002 of the staple cartridge 10000 when thefiring member 10052 is retracted. Once the firing member 10052 has beensufficiently retracted, the anvil can be re-opened, the tissue thicknesscompensator 10020 can be detached from the support portion 10010, andthe remaining non-implanted portion of the expended staple cartridge10000, including the support portion 10010, can be removed from thestaple cartridge channel 10070.

After the expended staple cartridge 10000 has been removed from thestaple cartridge channel, further to the above, a new staple cartridge10000, or any other suitable staple cartridge, can be inserted into thestaple cartridge channel 10070. In various embodiments, further to theabove, the staple cartridge channel 10070, the firing member 10052,and/or the staple cartridge 10000 can comprise co-operating featureswhich can prevent the firing member 10052 from being advanced distally asecond, or subsequent, time without a new, or unfired, staple cartridge10000 positioned in the staple cartridge channel 10070. Moreparticularly, referring again to FIG. 258, as the firing member 10052 isadvanced into contact with the sled 10050 and, when the sled 10050 is inits proximal unfired position, a support nose 10055 of the firing member10052 can be positioned on and/or over a support ledge 10056 on the sled10050 such that the firing member 10052 is held in a sufficient upwardposition to prevent a lock, or beam, 10054 extending from the firingmember 10052 from dropping into a lock recess defined within the staplecartridge channel. As the lock 10054 will not drop into the lock recess,in such circumstances, the lock 10054 may not abut a distal sidewall10057 of the lock recess as the firing member 10052 is advanced. As thefiring member 10052 pushes the sled 10050 distally, the firing member10052 can be supported in its upward firing position owing to thesupport nose 10055 resting on the support ledge 10056. When the firingmember 10052 is retracted relative to the sled 10050, as discussed aboveand illustrated in FIG. 261, the firing member 10052 can drop downwardlyfrom its upward position as the support nose 10055 is no longer restingon the support ledge 10056 of the sled 10050. In at least one suchembodiment, the surgical staple can comprise a spring 10058, and/or anyother suitable biasing element, which can be configured to bias thefiring member 10052 into its downward position. Once the firing member10052 has been completely retracted, as illustrated in FIG. 262, thefiring member 10052 cannot be advanced distally through the spent staplecartridge 10000 once again. More particularly, the firing member 10052can't be held in its upper position by the sled 10050 as the sled 10050,at this point in the operating sequence, has been left behind at thedistal end 10002 of the staple cartridge 10000. Thus, as mentionedabove, in the event that the firing member 10052 is advanced once againwithout replacing the staple cartridge, the lock beam 10054 will contactthe sidewall 10057 of the lock recess which will prevent the firingmember 10052 from being advanced distally into the staple cartridge10000 once again. Stated another way, once the spent staple cartridge10000 has been replaced with a new staple cartridge, the new staplecartridge will have a proximally-positioned sled 10050 which can holdthe firing member 10052 in its upper position and allow the firingmember 10052 to be advanced distally once again.

As described above, the sled 10050 can be configured to move the stapledrivers 10040 between a first, unfired position and a second, firedposition in order to eject staples 10030 from the support portion 10010.In various embodiments, the staple drivers 10040 can be contained withinthe staple cavities 10012 after the staples 10030 have been ejected fromthe support portion 10010. In certain embodiments, the support portion10010 can comprise one or more retention features which can beconfigured to block the staple drivers 10040 from being ejected from, orfalling out of, the staple cavities 10012. In various other embodiments,the sled 10050 can be configured to eject the staple drivers 10040 fromthe support portion 10010 with the staples 10030. In at least one suchembodiment, the staple drivers 10040 can be comprised of a bioabsorbableand/or biocompatible material, such as Ultem, for example. In certainembodiments, the staple drivers can be attached to the staples 10030. Inat least one such embodiment, a staple driver can be molded over and/oraround the base of each staple 10030 such that the driver is integrallyformed with the staple. U.S. patent application Ser. No. 11/541,123,entitled SURGICAL STAPLES HAVING COMPRESSIBLE OR CRUSHABLE MEMBERS FORSECURING TISSUE THEREIN AND STAPLING INSTRUMENTS FOR DEPLOYING THE SAME,filed on Sep. 29, 2006, is hereby incorporated by reference in itsentirety.

In various circumstances, further to the above, a compressible tissuethickness compensator can move, twist, and/or deflect relative to theunderlying rigid support portion of a staple cartridge. In variousembodiments, the support portion, and/or any other suitable portion ofthe staple cartridge, can comprise one or more features configured tolimit relative movement between the tissue thickness compensator and thesupport portion. As described above, at least a portion of the staples10030 can extend above the deck surface 10011 of the support portion10010 wherein, in certain circumstances, referring now to FIGS. 263 and264, lateral forces applied to a tissue thickness compensator 10120, forexample, can be resisted by the staples 10030 and/or the cleats 10013extending from the support portion 10010, for example. In variouscircumstances, the staples 10030 may tilt and/or bend within the staplecavities 10012 while resisting the lateral movement of the tissuethickness compensator 10120 wherein, in various embodiments, the staplecavities 10012 and the staples 10030 can be sized and configured tomaintain the relative alignment between the legs 10032 of the staples10030 and the forming pockets 10062 in the opposing anvil 10060 suchthat the staples 10000 are properly formed during the staple formingprocess. In various embodiments, the staples 10030 and/or the cleats10013 can be configured to prevent or at least limit lateral distortionwithin the tissue thickness compensator 10020, as illustrated in FIG.264. In at least one such embodiment, the staples 10030 and/or cleats10013, for example, can be configured to stiffen, or limit the lateraland/or longitudinal movement of, a first, or tissue-contacting, surface10021 of the tissue thickness compensator relative to a second, orbottom, surface 10029. In various embodiments, a staple cartridge,and/or a staple cartridge channel in which the staple cartridge ispositioned, can comprise at least one distortion minimizing member whichcan extend upwardly to limit the lateral and/or longitudinal movement,or distortion, of a tissue thickness compensator. A wrap at leastpartially surrounding a tissue thickness compensator, as discussedabove, may also prevent, or at least limit, the lateral and/orlongitudinal movement, or distortion, of the tissue thicknesscompensator.

In various embodiments, referring again to FIGS. 263 and 264, a tissuethickness compensator, such as tissue thickness compensator 10120, forexample, can comprise a core 10128 and a skin 10122. The skin 10122 andthe compressible core 10128 can be comprised of different materials or,alternatively, of the same material. In either event, the skin 10122 canhave a higher density than the core 10128. In circumstances where theskin 10122 comprises the top of the tissue thickness compensator 10120,the tips of the staple legs 10032 can be embedded in the skin 10122. Inembodiments wherein a skin comprises the bottom of the tissue thicknesscompensator 10120, the staple legs 10032 can extend through the skin andinto the core. In either event, the skin of the tissue thicknesscompensator can assist in holding the staple legs 10032 in alignmentwith the forming pockets 10062 of the anvil 10060. In variousembodiments, the skin 10122 can comprise a density which isapproximately 10% greater than the density of the core 10128,approximately 20% greater than the density of the core 10128,approximately 30% greater than the density of the core 10128,approximately 40% greater than the density of the core 10128,approximately 50% greater than the density of the core 10128,approximately 60% greater than the density of the core 10128,approximately 70% greater than the density of the core 10128,approximately 80% greater than the density of the core 10128,approximately 90% greater than the density of the core 10128, and/orapproximately 100% greater than the density of the core 10128, forexample. In various embodiments, the skin 10122 can comprise a densitywhich is more than the density of the core 10128 and less than twice thedensity of the core 10128, for example. In various embodiments, the skin10122 can comprise a density which is over twice the density of the core10128, for example. In various embodiments, further to the above, theskin 10122 and the core 10128 can be formed, or manufactured,simultaneously. In at least one such embodiment, a fluid comprising anysuitable material disclosed herein can be poured into a dish or moldand, while the fluid solidifies, the fluid can form a skin, or layer,which has a higher density than the remainder of the material. Invarious embodiments, multiple layers within a material can be formed byutilizing a process in which one or more subsequent layers of materialare poured onto a previously cured layer. In certain embodiments, two ormore layers can be bonded to each other with an adhesive, for example.In some embodiments, two or more layers can be attached to each other byone or more fasteners and/or one or more mechanical interlockingfeatures, for example. In at least one such embodiment, adjacent layerscan be connected together by one or more dovetail joints, for example.In certain embodiments, the skin can comprise a sealed surface which canprevent, or at least limit, the flow of fluid therethrough. In certainother embodiments, the skin can comprise an open cell porous structure,for example.

In various embodiments, further to the above, the skin can be cut off ofthe tissue thickness compensator. In at least one embodiment, the tissuethickness compensator can be cut from a larger block of material suchthat the tissue thickness compensator does not comprise a skin. In atleast one such embodiment, the tissue thickness compensator can becomprised of a homogenous, or at least substantially homogeneous,material, comprising large pores, for example.

In various embodiments, a staple cartridge can comprise a plurality ofstaple cavities each containing a staple positioned therein wherein thestaple cavities can be arranged in a plurality of rows, and wherein ananvil positioned opposite the staple cartridge can comprise a pluralityof forming pockets which correspond to the staple cavities in the staplecartridge. Stated another way, the anvil can comprise a plurality offorming pocket rows wherein each forming pocket can be positionedopposite a staple cavity in the staple cartridge. In variousembodiments, each forming pocket can comprise two forming cupsconfigured to receive the staple legs 10032 of a staple 10030 whereineach forming cup is configured to receive a staple leg 10032 and form orcurl the staple leg 10032 toward the other staple leg 10032, forexample. In various circumstances, the legs 10032 may miss or notproperly enter into the forming cups and, as a result, the staple legs10032 may become malformed during the firing sequence. In variousembodiments described herein, an anvil can comprise an array, or grid,of forming pockets which are each configured to receive and form astaple leg. In at least one such embodiment, the array of formingpockets can comprise a quantity of forming pockets that exceeds thequantity of staples contained within the staple cartridge. In at leastone embodiment, a staple cartridge can comprise six longitudinal rows ofstaple cavities, for example, wherein the anvil can comprise six rows offorming pockets aligned with the six rows of staple cavities and, inaddition, forming pockets positioned intermediate the rows of formingpockets. For example, on one side of the anvil, the anvil can comprise afirst row of forming pockets which can be positioned over a first row ofstaple cavities, a second row of forming pockets which can be positionedover a second row of staple cavities that is adjacent to the first rowof staple cavities, and, in addition, a row of forming pocketspositioned intermediate the first row of forming pockets and the secondrow of forming pockets. In various embodiments, referring now to FIGS.276-279, an anvil 10260 can comprise six rows of forming pockets 10261which can be configured to be placed over six corresponding rows ofstaple cavities in the staple cartridge 10200. In at least one suchembodiment, rows of intermediate forming pockets 10262 can be positionedintermediate and/or adjacent to the rows of forming pockets 10261. Incertain embodiments, referring now to FIGS. 277, 278, and 280, eachforming pocket 10261 and 10262 can comprise two forming cups, whereineach forming cup can comprise a distal portion 10263 which can beconfigured to form or curl a staple leg 10032 proximally and a proximalportion 10264 which can be configured to form or curl a staple leg 10032distally. In various other circumstances, the staples 10030 can beformed in a variety of other ways. For example, a staple 10030 can beformed such that one leg 10032 is formed outwardly and the other leg10032 is formed inwardly (FIG. 281), or such that both legs 10032 areformed outwardly (FIG. 282) depending on, one, which forming cups thatthe staple legs 10032 enter into and/or, two, whether the legs 10032enter into the proximal portion 10263 or the distal portion 10064 ofeach forming cup, for example.

In various embodiments, further to the above, each forming pocket 10261and/or forming pocket 10262 can comprise a triangular or diamond-likeshape, for example. In at least one embodiment, each distal portion10263 and/or each proximal portion 10264 of the forming pockets cancomprise a triangular shape wherein, in at least one such embodiment,the triangular shapes of the distal portions 10263 and the proximalportions 10264 can be arranged such that they have vertices pointing inopposite directions. In certain embodiments, an anvil can comprise anarray of substantially square forming pockets, for example. In at leastone such embodiment, the forming surface of each square forming pocketcan comprise an arcuate surface that extends between the sides of thesquare. In some embodiments, an anvil can comprise an array of circularor spherical dimples, for example. In various embodiments, further tothe above, the forming pockets 10261 can be positioned along one or morelines and, similarly, the forming pockets 10262 can also be positionedalong one or more lines. In various other embodiments, the formingpockets 10261 and/or the forming pockets 10262 can be arranged in one ormore circular rows. In at least one such embodiment, the forming pockets10261 can be arranged along a primary circumference and the formingpockets 10262 can be arranged along a different circumference. Invarious embodiments, the primary circumference and the differentcircumference can be concentric, or at least substantially concentric.In certain embodiments, the forming pockets 10262 can be arranged alongan inner circumference positioned radially inwardly with respect to theprimary circumference and/or an outer circumference positioned radiallyoutwardly with respect to the primary circumference, for example. Invarious embodiments, the primary circumference can be defined by aprimary diameter, the inner circumference can be defined by an innerdiameter, and the outer circumference can be defined by an outerdiameter. In at least one such embodiment, the inner diameter can beshorter than the primary diameter and the outer diameter can be longerthan the primary diameter.

In various embodiments, as described above, an anvil can be moved froman open position to a closed position in order to compress tissueagainst the tissue thickness compensator of a staple cartridge, such astissue thickness compensator 10020, for example. In variouscircumstances, the tissue thickness compensator can be positionedadjacent to the support portion of the staple cartridge prior to thetissue thickness compensator being positioned relative to the tissue. Incertain embodiments, the tissue thickness compensator 10020 can be in aposition in which it abuts the support portion 10018 prior to the anvilbeing moved into its closed position. In certain other embodiments, thetissue thickness compensator 10020 can be in a position in which a gapis present between the tissue thickness compensator 10020 and thesupport portion 10018. In at least one such embodiment, the anvil candisplace the tissue and the tissue thickness compensator 10020downwardly until the tissue thickness compensator 10020 abuts thesupport portion 10018 wherein, at such point, the anvil can be movedinto is closed position and generate compression within the tissue. Inthe event that a surgeon is not satisfied with the positioning of thetissue between the anvil and the staple cartridge, the surgeon can openthe anvil, adjust the position of the anvil and the staple cartridge,and close the anvil once again. Owing to such positioning andre-positioning of the staple cartridge relative to the tissue, invarious circumstances, the distal end of the tissue thicknesscompensator 10020 may become dislodged from the support portion 10010,for example. In some such circumstances, the distal end of the tissuethickness compensator 10020 can contact the tissue and peel away from,or roll relative to, the support portion 10010. In various embodiments,as described in greater detail below, a staple cartridge can compriseone or more features configured to releasably retain a tissue thicknesscompensator to an underlying support portion of the staple cartridge

In various embodiments, referring now to FIG. 265, a staple cartridge10300 can comprise a support portion 10310, a tissue thicknesscompensator 10320 supported by the support portion 10310, and a distalend 10302 which includes a nose 10303 configured to releasably hold adistal end 10325 of the tissue thickness compensator 10320 in position.In at least one embodiment, the nose 10303 can comprise a slot 10305configured to receive the distal end 10325 of the tissue thicknesscompensator 10320. In various embodiments, the distal end 10325 can becompressed, or wedged, within the slot 10305 such that the distal end10325 can be held in place as the staple cartridge 10300 is positionedrelative to the tissue. In at least one such embodiment, the slot 10305can be oriented in a direction which is parallel, or at leastsubstantially parallel, to the deck surface 10311 of the support portion10310. In various embodiments, the slot 10305 can be horizontal withrespect to the deck surface 10311. In various other embodiments,referring now to FIG. 266, a staple cartridge 10400 can comprise asupport portion, a tissue thickness compensator 10420 supported bysupport portion, and a distal end 10402 which includes a nose 10403configured to releasably hold the distal end 10425 of the tissuethickness compensator 10420 in position. In at least one embodiment, thedistal end 10425 can comprise a projection extending therefrom and thenose 10403 can comprise a vertical slot 10405 configured to receive theprojection of the distal end 10425. In various embodiments, the distalend 10425, and/or the projection extending therefrom, can be compressed,or wedged, within the slot 10405 such that the distal end 10425 can beheld in place as the staple cartridge 10400 is positioned relative tothe tissue. In certain embodiments, the tissue thickness compensator10420 can comprise a slot, such as slot 10429, for example, which can beconfigured to receive at least a portion of the nose 10403 therein. Inat least one embodiment, the slot 10405 can be oriented in a directionwhich is perpendicular, or at least substantially perpendicular, to thedeck surface 10411 of the support portion. In various embodiments,referring now to FIG. 267, a staple cartridge 10500 can comprise asupport portion, a tissue thickness compensator 10520 supported by thesupport portion, and a distal end 10502 which includes a nose configuredto releasably hold the distal end 10525 of the tissue thicknesscompensator 10520 in position. In at least one embodiment, the nose cancomprise a vertical slot 10505 configured to receive the distal end10525 of the tissue thickness compensator 10520. In various embodiments,the distal end 10525 can be compressed, or wedged, within the slot 10505such that the distal end 10525 can be held in place as the staplecartridge 10500 is positioned relative to the tissue.

In various embodiments, referring again to FIG. 265, the tissuethickness compensator 10320 can comprise a top surface 10324 which canbe positioned above the top surface 10304 of the nose 10303. Anotherexemplary embodiment in which the top surface of a tissue thicknesscompensator is positioned above the nose of the staple cartridge isillustrated in FIG. 238, wherein the top surface 10721 of the tissuethickness compensator 10720 is positioned above the top surface 10004 ofthe nose 10003, for example. In use, referring once again to FIG. 265,tissue can slide over the top surface 10304 of the nose 10303 and, insome circumstance, the tissue can contact the distal end 10325 of thetissue thickness compensator 10320 and can apply a force to the tissuethickness compensator 10320 tending to peel the tissue thicknesscompensator 10320 away from the support portion 10310. In theembodiments described herein, this peel force can be resisted by theportion of the distal end 10325 wedged within the nose 10303. In anyevent, once the tissue has been suitably positioned relative to thestaple cartridge 13000, an anvil can be rotated into a closed positionto compress the tissue and the tissue thickness compensator 10320against the support portion 10310. In at least one such embodiment, theanvil can be rotated into a position in which the anvil contacts the topsurface 10304 of the nose 10303 and, as a result, the anvil can beprevented from rotating further. In various circumstances, owing to thetop surface 10324 of the tissue thickness compensator 10320 beingpositioned above the top surface 10304 of the nose 10303, the topsurface 10324 can be pushed downwardly toward the support portion 10310as the anvil is being closed and, in some circumstances, the top surface10324 can be pushed below the top surface 10304 of the nose 10303, forexample. After the staples contained within the staple cartridge 10300have been deployed and the tissue thickness compensator 10320 has beenincised, as described herein, the support portion 10310 and the nose10303 can be moved away from the tissue thickness compensator 10320 suchthat the distal end 10325 of the tissue thickness compensator 10320 canslide out of the slot 10305.

As described above, an anvil, such as anvil 10060, for example, can berotated into a closed position in which the anvil 10060 contacts the topnose surface 10004 of a staple cartridge, such as staple cartridge10000, for example. Once the anvil has reached its closed position, theamount in which a tissue thickness compensator, such as tissue thicknesscompensator 10020, for example, is compressed will depend on, amongother things, the uncompressed thickness, or height, of the tissuethickness compensator and the thickness of the tissue. Referring now toFIGS. 236 and 237, a tissue thickness compensator 10920 can comprise atop surface which is flush, or at least substantially flush, with thetop surface 10004 of the nose 10003. In such embodiments, the topsurface of the tissue thickness compensator 10920 can be pushed belowthe top surface 10004 of the nose 10003. Referring now to FIGS. 241 and242, a tissue thickness compensator, such as tissue thicknesscompensator 10820, for example, can comprise a top surface 10821 whichis positioned below the top nose surface 10004 prior to the tissuethickness compensator 10820 being compressed by the tissue T and anvil10060. In the circumstances where the tissue T is relatively thin, asillustrated in FIGS. 239 and 240, the tissue thickness compensator 10920may undergo relatively little compression. Referring now to FIGS. 241and 242, the tissue thickness compensator 10820 may undergo a largercompression when the tissue T is relatively thicker. In thecircumstances where the tissue T has both thin sections and thickersections, as illustrated in FIGS. 243 and 244, the tissue thicknesscompensator 10820 may be compressed a larger amount when it ispositioned under the thicker tissue T and a lesser amount when it ispositioned under the thinner tissue T, for example. In this way, asdescribed above, the tissue thickness compensator can compensate fordifferent tissue thicknesses.

In various embodiments, referring now to FIGS. 268-270, a surgicalstapling instrument can comprise, one, a cartridge channel 16670configured to receive a staple cartridge 16600 and, two, an anvil 16660pivotably coupled to the cartridge channel 16670. The staple cartridge16600 can comprise a support portion 16610 and a tissue thicknesscompensator 16620 wherein a distal end 16625 of the tissue thicknesscompensator 16620 can be releasably held to the support portion 16610 bya nose 16603 at the distal end 16602 of the staple cartridge 16600. Inat least one embodiment, the nose 16603 can comprise a slot 16605 andcan be comprised of a flexible material. In use, referring primarily toFIG. 269, the nose 16603 can be flexed downwardly in order to expand theopening of slot 16605. In certain embodiments, the nose 16603 cancomprise notches or cut-outs 16606 which can be configured to permit thenose 16603 to flex downwardly. In any event, in various circumstances,the expanded opening of the slot 16605 can facilitate the insertion ofthe distal end 16625 of the tissue thickness compensator 16620 into theslot 16605. Once the tissue thickness compensator 16620 has beensuitably positioned, the nose 16603 can be released and, owing to theresiliency of the material comprising the nose 16603, the nose 16603 canreturn, or at least substantially return, to its unflexed condition andtrap the distal end 16625 of the tissue thickness compensator 16620against the deck surface 16611, as illustrated in FIG. 270. In use,similar to the above, the distal end 16625 can be pulled out of the slot16605 when the support portion 16610 is moved away from the stapledtissue. In various circumstances, the flexible nose 16603 can beconfigured to deflect as the tissue thickness compensator 16620 isdetached from the support portion 16610. In various embodiments,referring again to FIG. 270, the tissue thickness compensator 16620 cancomprise a top surface 16621 which is aligned, or at least substantiallyaligned, with a top surface 16604 of the nose 16603.

In various embodiments, referring to FIG. 271, a surgical staplinginstrument can comprise, one, a channel 10770 configured to receive astaple cartridge 10700 and, two, an anvil 10760 rotatably coupled to thechannel 10770. The staple cartridge 10700 can comprise a support portion10710 and a tissue thickness compensator 10720. In various embodiments,the tissue thickness compensator 10720 can be held in position by a nosesock 10703 which can be slid over the support portion 10710. In at leastone embodiment, referring primarily to FIG. 272, the nose sock 10703 cancomprise one or more side slots 10707 which can be configured toremovably receive one or more attachment rails extending along thesupport portion 10710, for example. In various embodiments, the tissuethickness compensator 10720 can be positioned intermediate the sideslots 10707. In certain embodiments, the nose sock 10703 can furthercomprise a distal end 10702 and a cavity 10706 defined in the distal end10702 wherein the cavity 10706 can also be configured to receive atleast a portion of the support portion 10710, for example, therein. Inuse, the nose sock 10703 can be slid onto the support portion 10710 in adistal to proximal direction. In various embodiments, the tissuethickness compensator 10720 can be removably mounted to the nose sock10703 such that, after staples have been fired through the tissuethickness compensator 10720, the tissue thickness compensator 10720 candetach from the nose sock 10703 as the support portion 10710 and thenose sock 10703 are moved away from the tissue thickness compensator10720. In various embodiments, the top surface 10721 of the tissuethickness compensator 10720 can be positioned below the top surface10704 of the nose 10703.

In various embodiments, referring now to FIGS. 273 and 274, a surgicalstapling instrument can comprise, one, a staple cartridge channel 11070configured to receive a staple cartridge 11000 and, two, an anvil 11060rotatably coupled to the channel 11070. The staple cartridge 11000 cancomprise a support portion 11010 and a tissue thickness compensator11020. In various embodiments, the tissue thickness compensator 11020can be held in position by a one or more longitudinal rails 11019extending from the deck 11011 of the support portion 11010. In at leastone embodiment, the longitudinal rails 11019 can be embedded within thetissue thickness compensator 11020. In certain embodiments, referringprimarily to FIG. 274, the tissue thickness compensator 11020 cancomprise a longitudinal recess 11029 which can be configured to receivethe longitudinal rails 11019. In at least one such embodiment, therecess 11029 can be sized and configured to receive the rails 11019 in apress-fit arrangement, for example. Such features, further to the above,can be configured to prevent, or at least limit, relative lateralmovement between the tissue thickness compensator 11020 and the supportportion 11010 and, in addition, limit the premature release of thetissue thickness compensator 11020 from the support portion 11010, forexample. In various embodiments, referring now to FIG. 275, a surgicalstapling instrument can comprise, one, a staple cartridge channel 11170configured to receive a staple cartridge 11100 and, two, an anvil 11160rotatably coupled to the channel 11170. The staple cartridge 11100 cancomprise a support portion 11110 and a tissue thickness compensator11120. In various embodiments, the tissue thickness compensator 11120can be held in position by one or more longitudinal rows of spikes, orteeth, 11119 extending from the deck 11111 of the support portion 11110.In at least one embodiment, the longitudinal rows of spikes 11119 can beembedded within the tissue thickness compensator 11120.

With regard to the embodiment illustrated in FIG. 273, further to theabove, the tissue thickness compensator 11020 of the staple cartridge11000 can be progressively released from the support portion 11010 asthe staples are ejected from the staple cavities 10012 defined therein.More particularly, further to the above, the staples positioned in thestaple cavities 10012 can be ejected sequentially between the proximalend 11001 of the staple cartridge 11000 and the distal end 11002 of thestaple cartridge 11000 such that, as the staples are being ejected, thestaples can apply an upward biasing force to the tissue thicknesscompensator 11020 which acts to push the tissue thickness compensator11020 off of the rails 11019. In such circumstances, the proximal end11006 of the tissue thickness compensator 11020 can be released from thesupport portion 11010 as the staples are ejected from the proximal-moststaple cavities 10012. The tissue thickness compensator 11020 can thenbe progressively released from the support portion 11010 as the staplesare progressively ejected from the support portion 11010 between theproximal end 11001 and the distal end 11002 of the staple cartridge11000. When the staples positioned within the distal-most staplecavities 10012 are ejected from the support portion 11010, the distalend 11007 of the tissue thickness compensator 11020 can be released fromthe support portion 11010. With regard to the embodiment illustrated inFIG. 275, the tissue thickness compensator 11120 can be progressivelyreleased from the spikes 1119 extending from the support portion 11110as the staples are progressively ejected from the staple cartridgebetween the proximal end 11101 and the distal end 11102.

As discussed above, a tissue thickness compensator can be progressivelyreleased from the support portion of a staple cartridge as the staplesare progressively ejected from the support portion and contact thetissue thickness compensator. In various embodiments, the legs of thestaple, such as staple legs 10032, for example, may be able to passthrough the tissue thickness compensator without releasing the tissuethickness compensator from the support portion. In such embodiments, thetissue thickness compensator may remain engaged with the support portionuntil the bases of the staples, such as bases 10031, contact the tissuethickness compensator and push it upwardly. In various embodiments,however, cleats and/or other retention features extending from thesupport portion, for example, may oppose the release of the tissuethickness compensator from the support portion. In certain embodiments,as described in greater detail below, a support portion can compriseretention features which can be configured to progressively release atissue thickness compensator from the support portion as the staples areprogressively fired from the staple cartridge. Referring now to FIG.283, a staple cartridge, such as staple cartridge 11200, for example,can comprise a support portion 11210 including retention features 11213which can be configured to releasably hold a tissue thicknesscompensator 11220 (FIG. 284) to the support portion 11210. In variousembodiments, the retention features 11213 can be positioned at the endsof each staple cavity 11212, for example, wherein each retention feature11213 can comprise a guide groove 11216 defined therein which isconfigured to slidably receive a staple leg 10032 of a staple 10030. Insuch embodiments, both the staple legs 10032 and the retention features11213 can be configured to releasably retain the tissue thicknesscompensator 11220 to the support portion 11210. In use, referring now toFIG. 284, staple drivers 10040 contained within the support portion11210 can be driven upwardly by a sled 10050, as described above,wherein the staple drivers 10040 can be configured to contact theretention features 11213, at least partially detach the retentionfeatures 11213 from the support portion 11210, and displace theretention features 11213 outwardly and away from the staples 10030 andthe staple cavities 11212. When the retention features 11213 aredetached from the support portion 11210 and/or displaced outwardly, asillustrated in FIG. 284, the retention features 11213 may no longer beable to retain the tissue thickness compensator 11220 to the supportportion 11210 and, as a result, the tissue thickness compensator 11220can be released from the support portion 11210. Similar to the above,the tissue thickness compensator 11220 can be progressively releasedfrom the support portion 11210 as the staples 10030 are progressivelyejected from the staple cartridge toward an anvil, such as anvil 11260,for example. In various embodiments, the staple drivers 10040 maycontact the retention features 11213 when the top surfaces of the stapledrivers 10040 become co-planar, or at least substantially co-planar,with the deck surface 11211 of the support portion 11210, for example.In such embodiments, the tissue thickness compensator 11220 may bereleased from the support portion 11210 at the same time as and/or justbefore the staples 10030 are formed to their fully-formed, orfully-fired, configuration. In at least one such embodiment, referringprimarily to FIG. 285, the drivers 10040 can be overdriven such thatthey are pushed above the deck surface 11211 to fully form the staples10030 and, during the process of being overdriven, break the retentionfeatures 11213 away from the support portion 11210. In variousembodiments, referring again to FIG. 284, the retention features 11213may extend over, or overhang, into the staple cavities 11212 prior tobeing detached or displaced outwardly such that the drivers 10040 cancontact the retention features 11213 just as the drivers 10040 reach thedeck surface 11211. In any event, once the tissue thickness compensator11220 has been released from the support portion 11210, referring now toFIG. 285, the support portion 11210 can be moved away from the implantedtissue thickness compensator 11220.

As described above, a compressible tissue thickness compensator of astaple cartridge can be progressively released from a support portion,or cartridge body, of the staple cartridge as the staples are fired, ordeployed, from the staple cartridge. In various circumstances, such arelease can comprise a progressive loosening of the tissue thicknesscompensator from the support portion wherein, in some circumstances, acomplete detachment of the tissue thickness compensator from the supportportion may not occur until the anvil is opened and the support portionis moved away from the implanted tissue thickness compensator. Invarious embodiments, referring now to FIG. 289, a staple cartridge, suchas staple cartridge 11300, for example, can comprise a tissue thicknesscompensator 11320 which is releasably retained to a support portion11310. In at least one embodiment, the support portion 11310 cancomprise a plurality of retention members 11313 extending therefromwhich are configured to releasably compress and hold the longitudinalsides of the tissue thickness compensator 11320 to the support portion11310. In at least one such embodiment, each retention member 11313 cancomprise an inwardly-facing channel or slot 11316 which can beconfigured to receive the longitudinal sides of the tissue thicknesscompensator 11320 therein. In various circumstances, a plurality ofretention members 11313 can extend along a first longitudinal side ofthe support portion 11310 and a plurality of retention members 11313 canextend along a second longitudinal side of the support portion 11310wherein, in certain circumstances, the retention members 11313 can beconfigured to prevent, or at least limit, relative lateral movementbetween the tissue thickness compensator 11320 and the support portion11310 and, in addition, prevent, or at least limit, the prematurerelease of the tissue thickness compensator 11320 from the supportportion 11310. In various embodiments, the retention members 11313 canbe integrally formed with the support portion 11310 and, in at least oneembodiment, referring to FIG. 290, the retention members 11313 can beconfigured to detach, or at least partially detach, from the supportportion 11310 in order to allow the tissue thickness compensator 11320to detach from the support portion 11310, as illustrated in FIG. 291,for example. In certain embodiments, an anvil, such as anvil 11360, forexample, can be configured to compress the tissue thickness compensator11320 and, in response to pressure generated within the tissue thicknesscompensator 11320, the tissue thickness compensator 11320 can expandlaterally to at least partially detach, or disengage, the retentionmembers 11313 from the tissue thickness compensator 11320. In variousembodiments, the advancement of a knife member, discussed above, throughthe anvil 11360 and the staple cartridge 11300 can deploy the staplescontained therein and, simultaneously, squeeze the anvil 11360 and thestaple cartridge 11300 closer to one another which can apply an addedcompressive pressure to the tissue thickness compensator 11320 andthereby cause the retention members 11313 to sequentially detach as theknife member passes through the staple cartridge 11300.

In various embodiments, referring now to FIGS. 292-294, a staplecartridge, such as staple cartridge 11400, for example, can comprise atissue thickness compensator 11420 removably attached to a supportportion 11410. In at least one embodiment, the staple cartridge 11400can comprise one or more retainer bars 11413 which can be configured tohold the longitudinal sides of the tissue thickness compensator 11420 tothe deck surface 11411. In at least one such embodiment, each retainerbar 11413 can comprise opposing arms 11418 which can define a channel11416 therebetween. In such embodiments, one of the arms 11418 can beconfigured to extend over the tissue thickness compensator 11420 and theother arm 11418 can be configured to extend under a lip 11419 extendingfrom the support portion 11410. Referring primarily to FIG. 292, thechannel 11416 of each retainer bar 11413 can be sized and configured toapply a compressive force to the longitudinal sides of the tissuethickness compensator 11420 prior to the staple cartridge 11400 beingused. During use, referring primarily to FIG. 293, the staple cartridge11400 can be positioned within a staple cartridge channel and, once thestaple cartridge 11400 has been suitably positioned, an anvil, such asanvil 11460, for example, can be moved into a position in which it cancompress the tissue thickness compensator 11420. Similar to the above,the thickness tissue compensator 11420, when compressed, can expandlaterally, or outwardly, and, as a result, detach the retainer bars11413 from the staple cartridge 11400. In certain other embodiments, theclosing of the anvil 11460 may not detach, or may not completely detach,the retainer bars 11413 from the staple cartridge. In at least one suchembodiment, the advancement of a firing bar, described above, throughthe staple cartridge 11400 can deploy the staples 10030 from the supportportion 11410 and, simultaneously, squeeze the anvil 11460 and thestaple cartridge 11400 closer together to apply a compressive force tothe tissue thickness compensator 11420 that is sufficient to cause thetissue thickness compensator 11420 to expand laterally and detach theretainer bars 11413 from the staple cartridge 11400. Once the retainerbars 11413 have been detached from the staple cartridge 11400, referringto FIG. 294, the support portion 11410 can be moved away from theimplanted tissue thickness compensator 11420 and removed from thesurgical site. In certain alternative embodiments, referring now to FIG.295, a staple cartridge 11400′ can comprise retainer bars 11413′ which,similar to the above, can comprise arms 11418′ extending therefrom. Inat least one such embodiment, each of the arms 11418′ can comprise awedge-lock bevel 11417′ which can be configured to releasably latch theretainer bars 11413′ to the staple cartridge 11400′. More particularly,in at least one embodiment, the support portion 11410′ of the staplecartridge 11400′ can comprise undercuts 11419′ which, in co-operationwith the wedge-lock bevels 11417′, can be configured to releasablyretain the retainer bars 11413′ to the staple cartridge 11400 andinhibit the tissue thickness compensator 11420 from being prematurelydetached from the support portion 11410′. During use, similar to theabove, the retainer bars 11413′ can be detached from the staplecartridge 11400′ when a sufficient compressive force is applied to thetissue thickness compensator 11420, for example.

In various circumstances, as described above and referring again toFIGS. 259 and 260, the sled 10050 of the staple cartridge 10000 and thefiring member 10052 of a surgical stapling instrument can be moved fromthe proximal end 10001 of the staple cartridge 10000 to the distal end10002 (FIG. 219) of the staple cartridge 10000 in order to deploy thestaples 10030 from the support portion 10010. In at least one suchcircumstance, each staple 10030 can be moved from an unfired position toa fired position and ejected from the support portion 10010 to capturethe entirety of the tissue thickness compensator 10020 against thetissue positioned between the anvil 10060 and the staple cartridge10000. In certain circumstances, a surgeon may not need to fire all ofthe staples 10030 from the staple cartridge 10000 and the surgeon maystop the progression of the sled 10050 and the firing bar 10052 at apoint located intermediate the proximal end 10001 and the distal end10002 of the staple cartridge 10000. In such circumstances, the tissuethickness compensator 10020 may only be partially implanted to thetissue T and, in order to detach the unimplanted portion of the tissuethickness compensator 10020 from the support portion 10010, the surgeoncan pull the support portion 10010 away from the partially implantedtissue thickness compensator 10020 such that the unimplanted portionpeels or pulls off of the support portion 10010. While such embodimentsare suitable in various circumstances, an improvement is illustrated inFIGS. 300-302 wherein a tissue thickness compensator, such as tissuethickness compensator 11520 of staple cartridge 11500, for example, cancomprise a plurality of connected segments which can be configured todetach from one another. In at least one such embodiment, the tissuethickness compensator 11520 can comprise a first, or proximal-most,segment 11520 a, a second segment 11520 b removably connected to thefirst segment 11520 a, a third segment 11520 c removably connected tothe second segment 11520 b, a fourth segment 11520 d removably connectedto the third segment 11520 c, and a fifth segment 11520 e removablyconnected to the fourth segment 11520 d, for example. In variousembodiments, the tissue thickness compensator 11520 can comprise atleast one thin section 11529 positioned intermediate any two adjacentsegments 11520 a-11520 e which can be configured to define apre-determined rupture or separation point in which the tissue thicknesscompensator segments can separate from one another. In certainembodiments, a tissue thickness compensator can include any suitablearrangement of perforations, thin sections, and/or any other means forcreating a separation point within the tissue thickness compensator.Referring primarily to FIG. 301, an anvil 11560 is illustrated in aclosed position and the firing member 10052 is illustrated as havingbeen partially advanced through the staple cartridge 11500 such that thestaples 10030 underlying the first segment 11520 a, the second segment11520 b, and the third segment 11520 c have been fired to capture thetissue thickness compensator 11520 against the tissue T. In such aposition, the firing member 10052 has not yet been advanced to deploythe staples 10030 underlying the fourth segment 11520 d and the fifthsegment 11520 e, for example. Referring now to FIG. 302, the anvil 11560has been moved into an open position and the support portion 11510 ofthe staple cartridge 11500 has been moved away from the portion of thetissue thickness compensator 11520 that has been implanted. Asillustrated in FIG. 302, the thin section 11529 (FIG. 300) locatedintermediate the third segment 11520 c and the fourth segment 11520 dhas allowed the unimplanted portion of the tissue thickness compensator11520 to separate from the implanted portion.

In various embodiments, further to the above, a staple cartridge cancomprise a plurality of fasteners configured to releasably hold a tissuethickness compensator to a support portion of the staple cartridge. Incertain embodiments, the support portion can comprise a plurality ofapertures defined in the deck surface, for example, wherein thefasteners can extend through the tissue thickness compensator and can bereleasably retained in the support portion apertures. In use, thefasteners can be progressively released from the support portion as thestaples are progressively ejected from the support portion. In at leastone such embodiment, the fasteners can be implanted with the tissuethickness compensator and, in at least one embodiment, the fasteners canbe comprised of at least one bioabsorbable material, for example. Incertain embodiments, the fasteners can detach from the support portionafter the tissue thickness compensator has been at least partiallyimplanted and as the support portion is moved away from the implantedtissue thickness compensator. In various embodiments, referring now toFIGS. 323-325, a staple cartridge, such as staple cartridge 11600, forexample, can comprise a tissue thickness compensator 11620 releasablymounted to a support portion 11610 by a plurality of fasteners 11613.Each fastener 11613 can comprise a first end 11618 embedded withinand/or otherwise engaged with the tissue thickness compensator 11620, asecond end 11618 engaged with the support portion 11610, and a connector11616 which connects the first end 11618 to the second end 11618. Invarious embodiments, the fasteners 11613 can extend through a knife slot11615 defined in the support portion 11610. In use, the firing member10052, described above, can move a knife edge through the knife slot11615 in the support portion 11610 and incise the fasteners 11613 inorder to release the tissue thickness compensator 11620 from the supportportion 11610. In at least one such embodiment, the firing bar 10052 canbe advanced from a proximal end 11601 of the staple cartridge 11600 to adistal end 11602 of the staple cartridge 11600 in order to, one, advancethe sled 10050 distally and progressively fire the staples 10030, asdiscussed above, and, two, progressively incise and/or break thefasteners 11613 to progressively release the tissue thicknesscompensator 11620 from the support portion 11610. In certainembodiments, similar to the above, the tissue thickness compensator11620 can comprise a plurality of detachable segments 11620 a-11620 ewhich can each be held to support portion 11610 by one or more fasteners11613, for example. In the event that the firing member 10052 is stoppedintermediate the proximal end 11601 and the distal end 11602 of thestaple cartridge 11600, as illustrated in FIG. 324, the fasteners 11613can assist in holding the unimplanted portion of the tissue thicknesscompensator 11620 to the support portion 11610 after the anvil 11660 isopened and the support portion 11610 is moved away from the tissue T, asillustrated in FIG. 325. In various embodiments, further to the above,the cutting edge 10053 of the firing member 10052 can be configured toincise and/or break the fasteners 11613. In certain alternativeembodiments, referring now to FIGS. 327 and 328, a staple-deployingsled, such as sled 11650, for example, can comprise a knife edge 11653which can be configured to incise the connectors 11616 of the fasteners11613 as the sled 11650 traverses the staple cartridge 11600. In atleast one such embodiment, each connector 11616 can comprise acylindrical member extending between the T-shaped ends 11618 of thefasteners 11613 wherein the knife edge 11653 can comprise a concaveprofile 11653 which can be configured to receive the cylindricalconnector 11616, for example.

As discussed above, a staple cartridge can be loaded into a staplecartridge channel of a surgical stapling instrument. In variouscircumstances, a surgeon, or other clinician, may insert the staplecartridge into the staple cartridge channel by placing a downward forceonto the staple cartridge to lock the staple cartridge in place. In somesuch circumstances, the clinician may place their thumb, for example, onthe top surface of the staple cartridge to apply such a downward force.In various embodiments, the top surface of the staple cartridge maycomprise the top surface of a tissue thickness compensator wherein, asdescribed above, the tissue thickness compensator can be compressibleand, in certain embodiments, the downward force applied to tissuethickness compensator can cause the tissue thickness compensator tocompress to the point in which the clinician's thumb comes into contactwith the tips of the staples stored within the support portion. Invarious embodiments, a staple cartridge applicator can be utilized toinsert a staple cartridge into a staple cartridge channel which can beconfigured to prevent, or at least limit, the possibility of theclinician touching the staples in the staple cartridge. After the staplecartridge has been suitably positioned within the staple cartridgechannel, as described in greater detail below, the applicator can bedetached from the staple cartridge.

In certain embodiments, referring now to FIGS. 305 and 306, a staplecartridge applicator can comprise a rigid cover, such as cover 10080,for example, which can be attached to a staple cartridge 10000. Furtherto the above, the cover 10080 can be configured to prevent, or at leastinhibit, a clinician's thumb, for example, from contacting the tips ofthe staples 10030 positioned within the staple cartridge 10000 when thestaple cartridge 10000 is inserted into a staple cartridge channel.Referring now to FIGS. 307 and 308, the cover 10080 can extend over thetop surface 10021, or at least a portion of the top surface 10021, ofthe tissue thickness compensator 10020 and can include, one, a bottomsurface 10081 which can extend over and/or abut the tissue thicknesscompensator 10020 and, two, a top surface 10082 which can provide apushing surface for the clinician to apply a downward force thereto, forexample. In use, the clinician can grab a handle portion 10084 of thecover 10080, align the support portion 10010 of the staple cartridge10000 with the staple cartridge channel, and at least partially insertthe staple cartridge 10000 within the staple cartridge channel.Thereafter, the clinician can completely seat the staple cartridge 10000in the staple cartridge channel by applying the downward force to thetop surface 10082 of the cover 10880 which can, in various embodiments,transmit the downward force directly to the support portion 10010. In atleast one such embodiment, the cover 10080 can comprise proximalsupports 10087 which can extend downwardly and contact the deck surface10011 of the support portion. In certain embodiments, the cover 10080can further comprise a distal support portion 10083 which can beconfigured to abut the nose 10003. When a downward force is applied thecover 10080, the downward force can be transmitted through the proximalsupports 10087 and/or the distal support portion 10083 withouttransmitting, or at least without substantially transmitting, thedownward force to the support portion 10010 through the tissue thicknesscompensator 10020. In various circumstances, as a result of the above,the clinician may not directly contact the tissue thickness compensator10020. Also as a result of the above, the cover 10080 may not compress,or at least substantially compress, the tissue thickness compensator10020 as the staple cartridge 10000 is being inserted into the staplecartridge channel. In various embodiments, a cover can comprise anysuitable number of supports which are configured to transmit a downwardforce to the support portion without transmitting, or at leastsubstantially transmitting, the downward force through the tissuethickness compensator. In certain embodiments, the supports can extendaround the distal end, the proximal end, and/or the longitudinal sidesof the tissue thickness compensator. In some embodiments, the supportscan extend through the tissue thickness compensator. In at least onesuch embodiment, the supports can extend through apertures within thetissue thickness compensator and abut the deck of the support portion.In certain embodiments, at least some of the supports may not be incontact with the deck before the downward force is applied to the cover;however, in various embodiments, the cover can be configured to flex, ormove, downwardly until the supports contact the deck of the supportportion. At such point, the downward flexure, or movement, of the covercan be impeded, or at least substantially impeded, from flexing further.

As described above, the cover 10080 can be attached to the staplecartridge 10000 and can be used to manipulate the position of the staplecartridge 10000. In various embodiments, the cover 10080 can compriseany suitable number of gripping members which can be configured toreleasably hold the cover 10080 to the support portion 10010 of thestaple cartridge 10000, for example. In at least one such embodiment,the cover 10080 can further comprise one or more retention members, suchas latch arms 10088 and/or 10089, for example. In various embodiments,the latch arms 10089 can be configured to extend around the sides of thenose 10003 and engage the bottom surface 10009 (FIG. 306) of the nose10003. Similarly, the latch arms 10088 can extend around the sides oflock projections 10008 extending from the support portion 10010 andengage the bottom surfaces of the lock projections 10008. These latcharms, in various embodiments, can be configured to position the cover10080 over the zone or region in which the staples are stored within thesupport portion 10010. In any event, once the staple cartridge 10000 hasbeen suitably positioned, the cover 10080 can be detached from thestaple cartridge 10000. In at least one embodiment, the clinician canapply an upward lifting force to the handle 10084 in order to detach thedistal end of the cover 10080 from the distal end 10002 of the staplecartridge 10000. In at least one such embodiment, the latch arms 10088and 10089 can flex outwardly as the handle 10084 is lifted upwardly suchthat the latch arms 10088 and 10089 can flex around the lock projections10008 and the nose 10003, respectively. Thereafter, the proximal end ofthe cover 10080 can be lifted away from the proximal end 10001 of thestaple cartridge and the cover 10080 can be moved away from the staplecartridge 10000.

In certain embodiments, referring now to FIGS. 309 and 310, a staplecartridge applicator, such as staple cartridge applicator 10680, forexample, can be configured to position an upper tissue thicknesscompensator, such as tissue thickness compensator 10690, for example,relative to an anvil in addition to positioning a staple cartridge, suchas staple cartridge 10600, for example, within a staple cartridgechannel. Similar to the above, the applicator 10680 can comprise latcharms 10688 which can be releasably engaged with lock projections 10608extending from a support portion 10610 of the staple cartridge 10600such that the applicator 10680 can be maintained in position over atissue thickness compensator 10620 of the staple cartridge 10600. Invarious embodiments, the upper tissue thickness compensator 10690 can beremovably attached to the staple cartridge applicator 10680 such thatthe anvil of a surgical instrument, such as anvil 10060, for example,can be closed onto the applicator 10680, engage the tissue thicknesscompensator 10690, and detach the tissue thickness compensator 10690from the applicator 10680. In various embodiments, the tissue thicknesscompensator 10690 and/or the anvil 10060 can comprise one or moreretention features which can be configured to releasably hold the tissuethickness compensator 10690 to the anvil 10060. In at least one suchembodiment, the tissue thickness compensator 10690 can comprise alongitudinal rail 10695, for example, extending from the top surface10691 of the tissue thickness compensator 10690 which can be receivedwithin a longitudinal knife slot 10065 defined within the anvil 10060.In various embodiments, the tissue thickness compensator 10690 and thelongitudinal rail 10695 can be comprised of any suitable compressiblematerial, such as those described in the this patent application, forexample, wherein the longitudinal rail 10695 can be compressed and/orwedged within the knife slot 10065, for example. Once the anvil 10060has been engaged with the tissue thickness compensator 10690, the anvil10060 can be returned to an open position and, in such circumstances,the tissue thickness compensator 10690 can detach from the applicator10680. Thereafter, the applicator 10680 can be detached from the staplecartridge 10600 such that the anvil 10060 and the staple cartridge 10600can be positioned relative to the tissue that is to be stapled and/orincised. In use, a staple-deploying sled, such as sled 10050 (FIG. 236),for example, can be advanced distally through the staple cartridge 10600by a firing member 10052 (FIG. 236), for example, in order to eject thestaples from the staple cartridge 10060, as outlined above. As thestaples are deformed, each staple can capture a portion of the tissuethickness compensator 10690 against the top surface of the tissue and aportion of the tissue thickness compensator 10620 against the bottomsurface of the tissue. At the same time, the firing member 10052 canadvance a knife edge 10053 (FIG. 236) through the tissue thicknesscompensator 10620 and/or the tissue thickness compensator 10690 wherein,in at least one embodiment, the knife edge 10053 can be advanced throughthe longitudinal rail 10695 in order to incise the rail 10695 andprogressively detach the tissue thickness compensator 10690 from theanvil 10060. After the staples have been deployed, the anvil 10060 canbe re-opened and moved away from the implanted tissue thicknesscompensator 10690 and, similarly, the support portion 10610 of thestaple cartridge 10600 can be moved away from the implanted tissuethickness compensator 10620. In various embodiments, further to theabove, the tissue thickness compensator 10620 and/or the tissuethickness compensator 10690 can comprise a plurality of detachablesegments which can be configured to separate from one another in theevent that only portions of the tissue thickness compensators 10620 and10690 are implanted by the staples.

In various embodiments, further to the above, the applicator 10680 cancomprise one or more retention features which can be configured toreleasably hold the tissue thickness compensator 10690 to the applicator10680. In at least one such embodiment, referring primarily to FIG. 310,the applicator 10680 can comprise a longitudinal retention rail 10685which can be configured to be received in a longitudinal retention slot10694 defined in the bottom surface 10692 of the tissue thicknesscompensator 10690 in a press-fit manner, for example. In variouscircumstances, the retention rail 10685 and the retention slot 10694 canbe configured to retain the tissue thickness compensator 10690 to theapplicator 10680 until a sufficient upward lifting force is applied tothe tissue thickness compensator 10690 by the anvil 10060, as describedabove. In at least one such embodiment, the retention rail 10685extending from the applicator 10680 can further comprise end stops 10686positioned at the proximal and distal ends of the retention rail 10685which can be configured to prevent, or at least limit, relativelongitudinal movement between the tissue thickness compensator 10690 andthe applicator 10680. In certain embodiments, referring again to FIG.310, one or more adhesives, such as longitudinal adhesive strips 10693,for example, can be placed on the contact surface 10691 of the tissuethickness compensator 10690 such that, when the anvil 10060 contacts thetissue thickness compensator 10690, as described above, the adhesive canreleasably attach the tissue thickness compensator 10690 to the anvil10060. In various embodiments, one or more adhesives can be utilized inaddition to or in lieu of the compressible retention features describedabove, for example. In certain embodiments, one or more adhesives can beutilized to releasably hold a tissue thickness compensator to a staplecartridge applicator. In at least one embodiment, referring now to FIG.310A, the cover 10080, for example, can include one or more adhesivepads 12185 which can be configured to releasably retain an upper tissuethickness compensator, such as tissue thickness compensator 12190, forexample, to the top surface 10082 of the cover 10080. In at least onesuch embodiment, similar to the embodiments described above, an anvilcan be closed onto to the tissue thickness compensator 12190 to engagethe longitudinal retention rail 12195 of the tissue thicknesscompensator 12190. In certain embodiments, a release mechanism can bepositioned intermediate the tissue thickness compensator 12190 and thecover 10080 which can be utilized to break the adhesive bonds holdingthe tissue thickness compensator 12190 to the cover 10080 and detach thetissue thickness compensator 12190 from the cover 10080. In at least oneembodiment, the release mechanism can comprise a pull tab 12196 and aloop 12197 wherein the loop 12197 can comprise first and second endswhich are attached to the pull tab 12196. The loop 12197 can comprise asuture, for example, which can define a perimeter which circumscribesthe adhesive pads 12185 such that, when the pull tab 12196 is pulleddistally, the suture can slide between the tissue thickness compensator12190 and the cover 10080 and contact the tissue pads 12185. In suchcircumstances, the suture can at least one of separate the adhesive pads12185 from the tissue thickness compensator 12190, separate the adhesivepads 12185 from the cover 10080, and/or sever the adhesive pads 12185,for example.

In various embodiments, referring now to FIG. 311, a staple cartridgecan comprise a support portion 10710, for example, which, similar to theabove, can comprise a longitudinal knife slot 10715 extendingtherethrough. In at least one such embodiment, a staple cartridgeapplicator, such as applicator 10780, for example, can comprise alongitudinal retention and alignment member 10786 which can extend intothe knife slot 10715 in the support portion 10710. In certainembodiments, the retention member 10786 can be configured to engage thesidewalls of the knife slot 10715 in a press-fit manner, for example,such that the applicator 10780 can be releasably retained to the supportportion 10710. In various embodiments, although not illustrated, a firstportion of a tissue thickness compensator can be positioned on a firstside of the retention member 10786 and a second portion of the tissuethickness compensator can be positioned on an opposite, or second, sideof the retention member 10786. Similar to the above, the first andsecond portions of the tissue thickness compensator can be mounted tothe support portion 10710 of the staple cartridge via retention members10013, for example. Also similar to the above, an upper tissue thicknesscompensator 10790 can be removably mounted to the applicator 10780 via alongitudinal retention member 10785 extending from the loading surface10782 of the applicator 10780 wherein the retention member 10785 can bereleasably press-fit into a longitudinal slot 10794 defined in thebottom surface 10792 of the tissue thickness compensator 10790, forexample. In various embodiments, also similar to the above, the tissuethickness compensator 10790 can further comprise a longitudinalretention member 10795 extending from the top surface 10791 of thetissue thickness compensator 10790 which can be releasably retained inthe longitudinal knife slot 10065 defined in the anvil 10060, forexample. In at least one such embodiment, the longitudinal retentionmember 10795 can comprise a wedge-shaped cross-section comprising a topportion which is larger than a bottom portion, wherein the bottomportion can attach the retention member 10795 to the tissue thicknesscompensator 10790, for example.

In various embodiments, referring now to FIGS. 312 and 313, a staplecartridge 10800 comprising a support portion 10810 and a tissuethickness compensator 10820 can be loaded into a staple cartridgechannel with a staple cartridge applicator 10880, for example. Similarto the above, the staple cartridge applicator 10880 can also beconfigured to position an upper tissue thickness compensator 10890, forexample, relative to an anvil, such as anvil 10060, for example, suchthat, when the anvil 10060 is closed, the anvil 10060 can contact andengage the tissue thickness compensator 10890. In at least oneembodiment, the tissue thickness compensator 10890 can comprise aplurality of retention legs 10895 extending from the top surface 10891of the tissue thickness compensator 10890 which can be configured to beengage the anvil 10060 and releasably retain the tissue thicknesscompensator 10890 to the anvil 10060. In at least one such embodiment,the legs 10895 can be arranged in a longitudinal row wherein each leg10895 can comprise at least one foot configured to enter into and engagethe knife slot 10065 defined in the anvil 10060. In certain embodiments,some of the feet of legs 10895 can extend in one direction while otherfeet can extend in another direction. In at least one embodiment, someof the feet can extend in opposite directions. In any event, once theanvil 10060 has been engaged with the tissue thickness compensator10890, referring now to FIGS. 313 and 314, the anvil 10060 can bereopened and the clinician can move the staple cartridge applicator10880 away from the tissue thickness compensators 10820 and 10890.Thereafter, referring to FIG. 314A, the upper tissue thicknesscompensator 10890 can be positioned on a first side of the targetedtissue and the tissue thickness compensator 10820, which can comprise alower tissue thickness compensator, can be positioned on a second sideof the tissue. After the tissue thickness compensators 10820 and 10890have been suitably positioned, referring now to FIG. 314B, a knife edgeof a firing member, such as knife edge 10053, for example, can beadvanced through the tissue and the tissue thickness compensators. Invarious embodiments, referring now to FIG. 318, a staple cartridgeapplicator, such as applicator 12280, for example, can comprise a tissuethickness compensator 12290 detachably mounted thereto which can be,similar to the above, inserted into a staple cartridge channel, asillustrated in FIG. 319, and engaged by the anvil 10060 when the anvil10060 is moved into a closed position. In at least one such embodiment,the tissue thickness compensator 12290 can comprise a plurality ofretention members 12295 extending upwardly from the top surface 12291 ofthe tissue thickness compensator 12290 wherein each retention member12295 can comprise a plurality of flexible legs 12296 which can beconfigured to be inserted into the knife slot 10065 in the anvil 10060.Referring primarily to FIGS. 321 and 322, the flexible legs 12296 ofeach retention member 12295 can be separated by a gap 12298 such that,as the legs 12296 are inserted into the knife slot 10065, the legs 12296can flex inwardly and then resiliently return outwardly once theenlarged feet of the flexible legs 12296 have passed through the knifeslot 10065. In various embodiments, the enlarged feet of the flexiblelegs 12296 can flex behind opposing retention lips 12297 defined in theanvil 10060 and, as a result of the interaction of the legs 12296 andthe lips 12297, the tissue thickness compensator 12290 can be retainedto the anvil 10060. Thereafter, the staple cartridge applicator 12280can be moved away from the tissue thickness compensator 12290, asillustrated in FIG. 320. In use, once the tissue thickness compensator12290 has been implanted against the tissue by staples deployed fromstaple cartridge 10000, for example, the anvil 10060 can be re-openedand, as the anvil 10060 is moved away from the implanted tissuethickness compensator 12290, the legs 12296 of the retention members12995 can flex inwardly such that they can be pulled out of the knifeslot 10065.

In various embodiments, referring now to FIGS. 315 and 316, a tissuethickness compensator, such as tissue thickness compensator 11990, forexample, can be loaded longitudinally into an anvil, such as anvil11960, for example. More particularly, in at least one embodiment, thetissue thickness compensator 11990 can comprise one or more longitudinalrails 11995 which can be inserted into a distal opening in a knife slot11965 of the anvil 11960 and then pushed proximally until the tissuethickness compensator 11990 has been properly seated in the anvil 11960.In at least one such embodiment, each rail 11995 can comprise alongitudinal retention foot 11996 which can be positioned behind alongitudinal retention lip 11997 which at least partially defines theknife slot 11965, for example. As illustrated in FIG. 316, the feet11996 can extend in opposite directions in order to be positioned behindretention lips 11997 positioned on the opposite sides of the knife slot11965. In various embodiments, a longitudinal gap 11998 can be definedbetween the rails 11995 which can be configured to permit the rails11995 to flex inwardly toward one another when the tissue thicknesscompensator 11990 is detached from the anvil 11960. In certainembodiments, referring now to FIG. 317, a tissue thickness compensator,such as tissue thickness compensator 12090, for example, can compriseone or more lock arms 12098 which can extend around the sides of ananvil, such as anvil 12060, for example. In use, the lock arms 12098 canengage the anvil 12060 and releasably retain the tissue thicknesscompensator 12090 to the anvil 12060. In at least one such embodiment,the anvil 12060 can comprise one or more notches, or lock shoulders,12097, for example, which can each be configured to receive a footextending from a lock arm 12098. In use, the arms 12098 can flexoutwardly and detach from the anvil 12060 when the anvil 12060 is movedaway from the tissue thickness compensator 12090 after the tissuethickness compensator 12090 has been at least partially implanted.

As described above, a surgical stapling instrument can comprise a staplecartridge channel configured to receive a staple cartridge, an anvilrotatably coupled to the staple cartridge channel, and a firing membercomprising a knife edge which is movable relative to the anvil and thestaple cartridge channel. In use, a staple cartridge can be positionedwithin the staple cartridge channel and, after the staple cartridge hasbeen at least partially expended, the staple cartridge can be removedfrom the staple cartridge channel and replaced with a new staplecartridge. In some such embodiments, the staple cartridge channel, theanvil, and/or the firing member of the surgical stapling instrument maybe re-used with the replacement staple cartridge. In certain otherembodiments, a staple cartridge may comprise a part of a disposableloading unit assembly which can include a staple cartridge channel, ananvil, and/or a firing member, for example, which can be replaced alongwith the staple cartridge as part of replacing the disposable loadingunit assembly. Certain disposable loading unit assemblies are disclosedin U.S. patent application Ser. No. 12/031,817, entitled END EFECTORCOUPLING ARRANGMENTS FOR A SURGICAL CUTTING AND STAPLING INSTRUMENT,which was filed on Feb. 15, 2008, the entire disclosure of which isincorporated by reference herein. Referring now to FIG. 370, adisposable loading unit, such as disposable loading unit 12500, forexample, can comprise a support portion 12510, an anvil 12560 rotatablycoupled to the support portion 12510, and an elongate shaft 12570extending from the support portion 12510. Similar to the staplecartridges described herein, the support portion 12510 can comprise aplurality of staple cavities 10012 and a staple, such as a staple 10030,for example, positioned in each staple cavity 10012, for example. Thedisposable loading unit 12500 can further comprise a firing member 12552which can be advanced distally in order to move the anvil 12560 from anopen position, as illustrated in FIG. 370, to a closed position. Invarious embodiments, the disposable loading unit 12500 can furthercomprise a tissue thickness compensator 12520 positioned on and/orattached to the support portion 12510 wherein, when the anvil 12560 isin its closed position, the anvil 12560 can be positioned opposite thetissue thickness compensator 12520 and, in some embodiments, the anvil12560 can at least partially compress the tissue thickness compensator12520 when the anvil 12560 is in its closed position. In either event,the firing member 12552 can be advanced further in order to eject thestaples from the support portion 12510. As the staples are ejected, thestaples can be deformed by the anvil 12560 and trap at least a portionof the tissue thickness compensator 12520 therein. Thereafter, thefiring member 12552 can be retracted proximally, the anvil 12560 can bere-opened, and the support portion 12510 can be moved away from theimplanted tissue thickness compensator 12520.

In various embodiments, further to the above, the tissue thicknesscompensator 12520 can be detachably mounted to the support portion12510. In at least one such embodiment, the support portion 12510 cancomprise a longitudinal retention rail 12526 mounted to each sidethereof wherein each rail 12526 can comprise one or more apertures 12528which can be configured to receive at least a portion of the tissuethickness compensator 12520 therein. Once the tissue thicknesscompensator 12520 has been at least partially implanted, the tissuethickness compensator 12520 can pull out of the apertures 12528 as thesupport portion 12510 is moved away. In various embodiments, referringnow to FIGS. 371-373, a disposable loading unit 12600 can comprise asupport portion 12610, a tissue thickness compensator 12620 detachablymounted to the support portion 12610, and one or more retention rails12626 which can be configured to extend under the tissue thicknesscompensator 12620 and mount the tissue thickness compensator 12620 tothe support portion 12610. Each retention rail 12626 can comprise aplurality of retention hooks 12628, for example, which can be engaged tothe support portion 12610 via retention slots 12614, for example,defined in the support portion 12610. In use, in at least one suchembodiment, the tissue thickness compensator 12620 can be configured todetach from the retention rails 12626 after the tissue thicknesscompensator 12620 has been at least partially implanted and the supportportion 12610 is moved away from the tissue thickness compensator 12620.In various embodiments, referring now to FIGS. 374-376, a disposableloading unit 12700 can comprise one or more retention rails 12726 whichcan each comprise a bottom bar 12725 which can extend under the tissuethickness compensator 12720 and a top bar 12727 which can extend overthe top surface 12621 of the tissue thickness compensator 12620. Incertain embodiments, the tissue thickness compensator 12620 can be atleast partially compressed between the top bars 12727 and the bottombars 12725 such that the retention rails 12726 can releasably hold thetissue thickness compensator 12620 relative to the support portion12610. In at least one such embodiment, each retention rail 12726 cancomprise one or more retention hooks 12728 which can be engaged with thesupport portion 12610 to retain the retention rails 12726 to the supportportion 12610.

In various embodiments, referring now to FIGS. 377 and 378, a disposableloading unit 12800 can comprise a retention member 12822 which can beconfigured to mount a tissue thickness compensator 12620 to the supportportion 12610. In at least one such embodiment, the retention member12822 can comprise a sheet of material positioned against the decksurface 12611 of the support portion wherein the tissue thicknesscompensator 12620 can be attached to the sheet of material by at leastone adhesive, for example. The retention member 12822 can furthercomprise a longitudinal retention rail 12825 configured to extenddownwardly into a knife slot 12615 defined in the support portion 12610.In at least one such embodiment, the retention rail 12825 can be sizedand configured such that it is compressed between the sidewalls of theknife slot 12615. In use, the firing member 12552 can comprise a knifeedge which can pass through the knife slot 12615 as the firing member12552 is advanced distally and transect the tissue thickness compensator12620 and the retention rail 12825 longitudinally. Also, in use, thestaples ejected from the support portion 12610 can penetrate theretention member 12822, the tissue thickness compensator 12820, and thetissue positioned between the tissue thickness compensator 12820 and theanvil 12560. In various embodiments, the retention member 12822 can becomprised of a biocompatible and/or bioabsorbable material. In certainembodiments, the retention member 12822 can be comprised of asufficiently compressible material to comprise a tissue thicknesscompensator underlying the tissue thickness compensator 12620. Invarious embodiments, referring now to FIGS. 379-381, a disposableloading unit 12900 can comprise a loading assembly including a bottomportion 12922 which can be removably attached to the support portion12610, a top portion 12990 which can be removably attached to the anvil12560, and a flexible joint 12991 connecting the bottom portion 12922and the top portion 12990. Similar to the above, a longitudinalretention rail 12825 can extend downwardly from the bottom portion 12922and into the knife slot 12615 defined in the support portion 12610 suchthat the bottom portion 12922 can be releasably retained to the supportportion 12610. Similarly, a longitudinal retention rail 12995 can extendupwardly from the top portion 12990 into a knife slot defined in theanvil 12560 such that the top portion 12990 can be releasably retainedto the anvil 12560. As illustrated in FIGS. 380 and 381, a tissuethickness compensator 12620 can be mounted to the bottom portion 12922of the loading assembly wherein, in order to position the tissuethickness compensator 12620 relative to the support portion 12610, aclinician could flex the top portion 12990 and the bottom portion 12922toward one another, position the loading assembly between the anvil12560 and the support portion 12610, and release the flexed loadingassembly such that it can resiliently expand and bias the top portion12990 against the anvil 12560 and the bottom portion 12922 against thesupport portion 12610. In at least one embodiment, referring now toFIGS. 382-384, the loading assembly can further comprise one or morelatch hooks, such as latch hooks 12994, for example, extending therefromwhich can be configured to releasably connect the top portion 12990 tothe anvil 12560 and/or releasably connect the bottom portion 12922 tothe support portion 12610.

In various embodiments, referring now to FIG. 385, a disposable loadingunit 15900, for example, can comprise an anvil 15960 and a staplecartridge channel 15970 wherein the staple cartridge channel 15970 canrotate relative to the anvil 15960. In at least one such embodiment, theanvil 15960 may not be able to rotate. In certain embodiments, tissuecan be positioned between the anvil 15960 and the staple cartridgechannel 15970 and, thereafter, the staple cartridge channel 15970 can berotated toward the tissue to clamp the tissue against the anvil. In atleast one such embodiment, the disposable loading unit 15900 can furthercomprise a tissue thickness compensator 15920 which can be configured tocontact the tissue.

As discussed above and referring to FIG. 332, a staple cartridge, suchas staple cartridge 10000, for example, can comprise a support portion10010 and a tissue thickness compensator 10020 wherein a plurality ofstaples 10030 can be at least partially stored in the support portion10010 and can extend into the tissue thickness compensator 10020 whenthe staples 10030 are in their unfired position. In various embodiments,the tips of the staples 10030 do not protrude from the tissue thicknesscompensator 10020 when the staples 10030 are in their unfired positions.As the staples 10030 are moved from their unfired positions to theirfired positions by the staple drivers 10040, as discussed above, thetips of the staples 10030 can penetrate through the tissue thicknesscompensator 10020 and/or penetrate through the upper layer, or skin,10022. In certain alternative embodiments, the tips of the staples 10030can protrude through the top surface of the tissue thickness compensator10020 and/or skin 10022 when the staples 10030 are in their unfiredposition. In either event, the staples 10030, as they extend upwardlyout of the support portion 10010 prior to being deployed, may tiltand/or deflect relative to the support portion, as also discussed above.In various embodiments, referring now to FIG. 329, a staple cartridge,such as staple cartridge 13000, for example, can comprise a plurality ofguide members, or retainers, which can be configured to limit relativemovement between the support portion 13010 of the staple cartridge 13000and the tips of the staples positioned therein. Referring primarily toFIG. 330, the staple cartridge 13000 can comprise a tissue thicknesscompensator 13020 mounted to a support portion 13010 and, in addition, aplurality of pledgets 13022 attached to the top surface 13021 of thetissue thickness compensator 13020. In various embodiments, each pledget13022 can comprise a plurality of apertures 13029 defined therein whichcan be configured to slidably receive and/or guide the legs 13022 of astaple 13030 therein. In addition to or in lieu of the apertures, apledget can comprise any suitable opening such as a slot, guide, and/orgroove, for example, which can be configured to slidably receive and/orguide the legs 13022. In certain embodiments, as illustrated in FIG.330, the tips of the staple legs 13032 can be positioned within theapertures 13029 when the staples 13030 are in their unfired positions.In at least one such embodiment, the tips of the staple legs 13032 canprotrude above the pledgets 13022 when the staples are in their unfiredposition. In certain other embodiments, the tips of the staple legs13032 may be positioned just below the pledgets 13022 when the staples13030 are in their unfired positions such that, when the staples 13030are moved upwardly through the tissue thickness compensator 13020, thestaple legs 13032 can enter into the apertures 13029 of the pledgets13022 and slide therethrough. In any event, when the legs 13032 of thestaples 13030 are positioned within the pledgets, the lateral and/orlongitudinal movement of the staple legs 13032 can be limited withoutpreventing the upward movement of the staple legs 13032 when the staples13030 are deployed. When the staples 13030 are deployed, referring nowto FIG. 331, the staple legs 13032 can slide upwardly through thepledgets 13022 to penetrate the tissue T, contact an anvil positionedopposite the staple cartridge 13030, and deform downwardly to capturethe tissue T and the tissue thickness compensator 13030 therein.

In various embodiments, further to the above, the pledgets 13022 can beattached to the tissue thickness compensator 13020 utilizing at leastone biocompatible and/or bioabsorbable adhesive, for example. In certainembodiments, the pledgets 13022, and/or a retention member extendingfrom each pledget, can be at least partially embedded within the tissuethickness compensator 13020. In at least one such embodiment, the tissuethickness compensator 13020 can comprise pockets defined therein whichare configured to at least partially receive a pledget 13022. In certainembodiments, the tissue thickness compensator 13020 can be integrallymolded, or formed around, the pledgets 13022 during a moldingmanufacturing process. In various embodiments, the pledgets 13022 maycomprise discrete retainers that can move independently of one another.In at least one embodiment, referring primarily to FIG. 330, eachpledget 13022 can comprise interlocking and/or keyed features which canbe configured to permit and, to a certain extent, limit relative lateraland longitudinal movement between the pledgets 13022. In at least onesuch embodiment, each pledget 13022 can comprise a projection 13026 andone or more recesses 13027, for example, wherein the projection 13026 ofa first pledget 13022 can be positioned within and/or aligned withrespect to the recesses of 13027 of adjacent second and third pledgets13022. In various embodiments, gaps can be present between adjacentpledgets 13022 which can permit the pledgets 13022 to move or sliderelative to one another until they contact an adjacent pledget 13022. Incertain embodiments, the pledgets 13022 can be loosely interconnected.In various embodiments, the pledgets 13022 can be detachably connectedto one another. In at least one such embodiment, the pledgets 13022 canbe manufactured as a sheet of interconnected pledgets wherein, when asufficient force is applied to the sheet, one or more of the pledgets13022 can break away from the others. In certain embodiments, referringagain to FIG. 329, a first sheet 13024 of pledgets 13022 can bepositioned on a first side of a longitudinal slot 13025 and a secondsheet 13024 of pledgets 13022 can be positioned on a second side of slot13025. In at least one embodiment, further to the above, thelongitudinal slot 13025 extending through the tissue thicknesscompensator 13020 can be configured to facilitate the passage of a knifeedge of a firing member through the tissue thickness compensator 13020and, as the firing member passes thereby, the firing member can apply acompressive force to the sheets 13024 and separate or singulate at leastsome of the pledgets 13022.

In various embodiments, the pledgets 13022 can be comprised of abiocompatible and/or bioabsorbable plastic, for example. In certainembodiments, the pledgets 13022 can be comprised of a solid material, asemi-solid material, and/or a flexible material, for example. In certainembodiments, the pledgets 13022 can be embedded within a tissuethickness compensator such that the pledgets 13022 move with the tissuethickness compensator. In at least one such embodiment, the pledgets13022 can be sufficiently flexible such that they can flex with the topsurface of the tissue thickness compensator. In certain embodiments, thepledgets 13022 can be configured to remain embedded in the tissuethickness compensator while, in certain other embodiments, the pledgets13022 can be configured to pop out of, or detach from, the tissuethickness compensator. In various embodiments, the pledges 13022 cancomprise a top surface which is flush with the top surface of the tissuethickness compensator. In certain embodiments, the top surfaces of thepledgets 13022 can be positioned above and/or below the top surface ofthe tissue thickness compensator. In various embodiments, the topsurfaces of the pledgets 13022 can be disposed such that they arevisible when viewing the top surface of the tissue thickness compensatorwhile, in other embodiments, the top surfaces of the pledgets 13022 canbe positioned below a layer of the tissue thickness compensator, forexample. In certain embodiments, guide features can be molded into thetop surface of a tissue thickness compensator, for example. In at leastone such embodiment, the tissue thickness compensator may not comprise acomposite material and may comprise a unitary piece of material, forexample.

In various embodiments, referring now to FIG. 338, a staple cartridgecan comprise a tissue thickness compensator 13620 and a skin, or toplayer, 13621, for example. In at least one such embodiment, one or morepledgets, or retainers, 13622, for example, can be embedded in the skin13621. In certain embodiments, each retainer 13622 can comprise one ormore apertures 13629 defined therein which can be configured to receivethe staple legs 13032 of staples 13030 therein when the staples 13030are in their unfired position, as illustrated in FIG. 338. In use,further to the above, the staple legs 10032 can slide through theapertures 13629 when the staples 13030 are moved from their unfiredposition to their fired position until the bases 13031 of the staples13030 contact the tissue thickness compensator 13620 and compress atleast a portion of the tissue thickness compensator 13620 against thebottom surfaces of the pledgets 13622, for example. In variousembodiments, referring now to FIG. 333, a staple cartridge can comprisea tissue thickness compensator 13120 and a skin, or top layer, 13122,for example. In at least one such embodiment, the tissue thicknesscompensator 13120 can comprise conical bumps, projections, and/orprotrusions 13128, for example, which can extend upwardly from the topsurface 13121 of the tissue thickness compensator 13120. The projections13128 can be configured to receive and envelop the tips of the staplelegs 13032 of the staples 13030 when the staples 13030 are in theirunfired position, as illustrated in FIG. 333. The top layer 13122 canalso comprise conical bumps, projections, and/or protrusions 13129 whichcan be aligned, or at least substantially aligned, with the projections13128. In use, the staple legs 10032 can penetrate the projections 13128and 13129 and emerge from the tissue thickness compensator 13120. Invarious embodiments, referring now to FIG. 337, a staple cartridge cancomprise a tissue thickness compensator 13520 and a skin, or top layer,13522, for example. In at least one such embodiment, the skin 13522 cancomprise conical bumps, projections, and/or protrusions 13529, forexample, which can extend upwardly from the top surface 13521 of thetissue thickness compensator 13520. Similar to the above, theprojections 13529 can be configured to receive and envelop the tips ofthe staple legs 13032 of the staples 13030 when the staples 13030 are intheir unfired position, as illustrated in FIG. 337. In use, the staplelegs 10032 can penetrate the projections 13529 and emerge from the skin13522.

In various embodiments, referring now to FIG. 334, a staple cartridgecan comprise a tissue thickness compensator 13220 and a skin, or toplayer, 13222, for example. In at least one such embodiment, the tissuethickness compensator 13220 can comprise conical dimples and/or recesses13128, for example, which can extend downwardly into the top surface13221 of the tissue thickness compensator 13220. In various embodiments,the tips of the staple legs 13032 can extend through the recesses 13128when the staples 13030 are in their unfired position, as illustrated inFIG. 334. In at least one embodiment, the top layer 13222 can alsocomprise conical dimples and/or recesses 13229 which can be aligned, orat least substantially aligned, with the recesses 13228. In variousembodiments, referring now to FIG. 335, a staple cartridge can comprisea tissue thickness compensator 13320 and a skin, or top layer, 13322,for example. In at least one such embodiment, the skin 13320 cancomprise thick portions 13329 which can extend downwardly into the topsurface 13321 of the tissue thickness compensator 13320. In variouscircumstances, the thick portions 13329 can be configured to receive atleast a portion of the staple legs 13032 of the staples 13030 thereinwhen the staples 13030 are in their unfired position, as illustrated inFIG. 335. In such embodiments, the thick portions 13329 can hold thestaple legs 13032 in position such that the legs 13032 are aligned, orat least substantially aligned, with the staple-forming pockets of ananvil positioned opposite the tissue thickness compensator 13320. Invarious embodiments, referring now to FIG. 336, a staple cartridge cancomprise a tissue thickness compensator 13420 and a skin, or top layer,13422, for example. In at least one such embodiment, the skin 13422 cancomprise thick portions 13429 which can extend upwardly from the topsurface 13421 of the tissue thickness compensator 13420. In variouscircumstances, the thick portions 13429 can be configured to receive atleast a portion of the staple legs 13032 of the staples 13030 thereinwhen the staples 13030 are in their unfired position, as illustrated inFIG. 336. In such embodiments, the thick portions 13429 can hold thestaple legs 13032 in position such that the legs 13032 are aligned, orat least substantially aligned, with the staple-forming pockets of ananvil positioned opposite the tissue thickness compensator 13420.

In various embodiments, referring now to FIGS. 339 and 340, a staplecartridge can comprise a tissue thickness compensator 13720 and a skin,or top layer, 13721, for example. In at least one such embodiment, thetissue thickness compensator 13720 can comprise pyramidal and/or steppedbumps, projections, and/or protrusions 13728, for example, which canextend upwardly from the top surface 13721 of the tissue thicknesscompensator 13720. The projections 13728 can be configured to receiveand envelop the tips of the staple legs 13032 of the staples 13030 whenthe staples 13030 are in their unfired position, as illustrated in FIG.340. Similarly, the top layer 13721 can comprise pyramidal and/orstepped bumps, projections, and/or protrusions 13729 which can bealigned, or at least substantially aligned, with the projections 13728.In various embodiments, the skin 13721 can further comprise one or moreteeth 13727 extending upwardly from the projections 13729 which can beconfigured to engage tissue positioned against the top layer 13721 andprevent, or at least limit, relative lateral and/or longitudinalmovement between the tissue, the top layer 13721, and/or the tips of thestaple legs 13032. In use, the staple legs 13032 can penetrate theprojections 13728 and 13729 and emerge from the tissue thicknesscompensator 13720 when the staples 13030 are moved from their unfiredpositions to their fired positions. In various embodiments, referringnow to FIGS. 341 and 342, a staple cartridge can comprise a tissuethickness compensator 13820 and a skin, or top layer, 13821, forexample. In at least one such embodiment, the tissue thicknesscompensator 13820 can comprise pyramidal and/or stepped bumps,projections, and/or protrusions 13828, for example, which can extendupwardly from the top surface 13821 of the tissue thickness compensator13820. The projections 13828 can be configured to receive and envelopthe tips of the staple legs 13032 of the staples 13030 when the staples13030 are in their unfired position, as illustrated in FIG. 342.Similarly, the top layer 13821 can comprise pyramidal and/or steppedbumps, projections, and/or protrusions 13829 which can be aligned, or atleast substantially aligned, with the projections 13828. In variousembodiments, the top layer 13821 can further comprise one or more teeth13827 extending downwardly into the tissue thickness compensator 13820which can be configured to prevent, or at least limit, relative lateraland/or longitudinal movement between the top layer 13821 and the tissuethickness compensator 13820, for example. In use, the staple legs 10032can penetrate the projections 13828 and 13829 and emerge from the tissuethickness compensator 13820 when the staples 13030 are moved from theirunfired positions and their fired positions.

In various embodiments, referring now to FIG. 343, a staple cartridgecan comprise a tissue thickness compensator, such as tissue thicknesscompensator 13920, for example, which can include ridges 13923 andvalleys 13924 defined therein wherein, in at least one embodiment, thevalleys 13924 can be defined between the ridges 13923. In variousembodiments, each ridge 13923 can comprise the same height,substantially the same height, or different heights. Similarly, eachvalley 13924 can comprise the same depth, substantially the same depth,or different depths. In various embodiments, a plurality of staples13030 can be at least partially stored within the tissue thicknesscompensator 13920 such that the tips of the staples 13030 can bepositioned within the ridges 13923. In at least one such embodiment, thestaple legs 13032 of the staples 13030 may not protrude from the tissuethickness compensator 13920 and/or a skin, or top layer, 13921 attachedto the tissue thickness compensator 13920, for example, when the staples13030 are stored in their unfired position. In various embodiments, theridges 13923 and/or the valleys 13924 can extend laterally across thestaple cartridge. In at least one such embodiment, the staple cartridgecan comprise a longitudinal knife slot wherein the ridges 13923 and thevalleys 13924 can extend in a direction which is transverse and/orperpendicular to the knife slot. In various circumstances, the ridges13923 can be configured to hold the tips of the staple legs 13032 inposition until the staples 13030 are moved from their unfired positioninto their fired position. In various embodiments, referring now to FIG.344, a tissue thickness compensator, and/or a skin covering a tissuethickness compensator, can comprise longitudinal ridges and/or valleys.In at least one such embodiment, a tissue thickness compensator cancomprise a top surface defined by ridges 14023 and valleys 14024,wherein the valleys 14024 can be defined between the ridges 14023, forexample. In various embodiments, the tissue thickness compensator cancomprise a skin 14021 which can include a plurality of apertures 14029defined therein which can each be configured to receive a staple leg13032. In certain embodiments, the apertures 14029 can be defined in theridges 14023 wherein the tips of the staple legs 13032 may be positionedbelow the peaks 14028 of the ridges 14029, positioned flush with thepeaks 14028, and/or positioned above the peaks 14028. In certainembodiments, in addition to or in lieu of the above, the apertures 14029can be defined in the valleys 14024, for example. In certainembodiments, each aperture can be surrounded, or at least partiallysurrounded, by an embossment, for example, which can strengthen the skinand/or tissue thickness compensator surrounding the apertures. In anyevent, further to the above, the skin 14021 can be attached to a tissuethickness compensator in any suitable manner, including using at leastone adhesive, for example.

As described above and referring again to FIG. 233, a surgical staplinginstrument can comprise an anvil, such as anvil 10060, for example,which can be moved between an open position and a closed position inorder to compress tissue T against the tissue thickness compensator10020 of a staple cartridge 10000, for example. In variouscircumstances, the anvil 10060 can be rotated toward the staplecartridge 10000 until its downward movement is stopped by some portionof the staple cartridge 10000 and/or some portion of the channel inwhich the staple cartridge 10000 is positioned. In at least one suchcircumstance, the anvil 10060 can be rotated downwardly until itsdownward movement is resisted by the nose 10003 of the staple cartridge10000 and/or the tissue T positioned intermediate the nose 10003 and thestaple cartridge 10000. In some circumstances, the anvil 10060 maysufficiently compress the tissue thickness compensator 10020 to permitthe tissue T to contact the tips of the staples 10030. In certaincircumstances, depending on the thickness of the tissue T, the anvil10060 may sufficiently compress the tissue thickness compensator 10020such that the anvil 10060 comes into contact with the staples 10030 bythe time the anvil 10060 has reached its fully closed position. Statedanother way, in such circumstances, the anvil 10060 may deform thestaples 10030 prior to the firing member 10052 being advanced into thestaple cartridge 10000 to fire the staples 10030. Such circumstances maybe acceptable in certain embodiments; however, referring now to FIGS.358 and 359, other embodiments are envisioned in which a distalgap-setting element, such as element 10059, for example, can be utilizedto limit the distance in which the anvil 10060 can be closed prior tothe firing bar 10052 being advanced into the staple cartridge 10000. Invarious embodiments, the element 10059 can extend upwardly from the topsurface 10021 of the tissue thickness compensator 10020 such that thedownward movement of the anvil 10060 can be arrested as the tissue T iscompressed against the element 10059 and a resistive force is generatedtherebetween. In use, as described above, the firing member 10052 can beadvanced distally into the staple cartridge 10000 toward the distal end10002 of the staple cartridge 10000 in order to eject the staples 10030from the support portion 10010. Simultaneously, the firing member 10052can engage the anvil 10060 and position the anvil 10060 a desireddistance from the deck surface 10011 (FIG. 218) of the support portion10010 over the staples 10030 being formed. In this way, the firingmember 10052 can control the distance, or gap, between thetissue-contacting surface of the anvil 10060 and the deck surface 10011at a particular location, wherein this particular location can beadvanced distally as the firing member 10052 is advanced distally. Invarious circumstances, this gap distance may be shorter than the gapbetween the anvil 10060 and the deck surface 10011 being controlled ordictated by the distal gap-setting element 10059 at the distal end ofthe tissue thickness compensator 10020. In various embodiments,referring now to FIG. 359, the knife edge 10053 of the firing member10052 can be configured to transect the distal gap-setting element 10059when the firing member 10052 reaches the distal end of the tissuethickness compensator 10020 such that, after the element 10059 has beentransected, the firing member 10052 can pull the anvil 10060 downwardlytoward the support portion 10010 and close the gap to the desired gapheight when firing the staples 10030 at the distal end of the staplecartridge 10000. In certain alternative embodiments, a distalgap-setting element can be configured to collapse as the firing memberapproaches the distal end of the staple cartridge. In at least one suchembodiment, the distal gap-setting element can comprise a column whichcan provide resistance to the anvil as described above and then suddenlybuckle once the buckling strength of the gap-setting element has beenreached when the firing member approaches the distal end of the staplecartridge. In at least one embodiment, this buckling force can beapproximately 10 lbf, for example. In certain embodiments, a gap settingelement can be configured to drop downwardly into the deck of thesupport portion when a force exceeding a predetermined amount is appliedto the gap setting element, for example. In certain other embodiments,the distal gap can be controlled by the nose of the staple cartridge. Inat least one such embodiment, the downward movement of the anvil 10060can be limited by the nose until the firing member has reached thedistal end of the cartridge wherein, at such point, the compressiveforce applied to the nose can cause the nose to collapse. In certainembodiments, the nose can comprise a cavity defined by cavity wallswhich can allow the cavity to collapse once the compressive forceapplied thereto has exceed a predetermined force. In at least one suchembodiment, the cavity can be defined by collapsible walls.

In various embodiments, as described above, an anvil, such as anvil10060, for example, can be moved between an open position and a closedposition in order to compress a tissue thickness compensator between theanvil and the support portion of a staple cartridge. In certaincircumstances, referring now to FIGS. 360 and 361, the tissue thicknesscompensator of a staple cartridge, such as tissue thickness compensator14120 of staple cartridge 14100, for example, may expand laterallyand/or longitudinally when the tissue thickness compensator 14120 iscompressed against a support portion 14110 of the staple cartridge14100. In certain embodiments, the ends and/or sides of the tissuethickness compensator 14120 may not be constrained by the supportportion 14110 and/or the anvil 10060 and, as a result, the tissuethickness compensator 14120 can expand in those directions withoutgenerating a compressive pressure, or at least an undesirablecompressive pressure, within the tissue thickness compensator 14120. Insuch embodiments, a firing member, such as firing member 10052 (FIG.236), for example, passing through the tissue thickness compensator14120 may not be unduly impeded by an undesirable compressive pressurewithin the tissue thickness compensator 14120, for example. In certainother embodiments, referring again to FIG. 360, the distal end 14125 ofthe tissue thickness compensator 14120 may be constrained by the nose14103 of the staple cartridge 14100, for example. In this particularembodiment, similar to the above, the distal end 14125 of the tissuethickness compensator 14120 may be constrained by the nose 14103 inorder to reduce the possibility of the tissue thickness compensator14120 from becoming prematurely detached from the support portion 14110.In any event, as a result of the above, a large internal pressure can begenerated within the distal end 14125 which can impede the advancementof the firing member 10052, especially when the firing member 10052reaches the distal end 14125. More particularly, in certaincircumstances, the firing member 10052 can push, plow, and/or displacethe tissue thickness compensator 14120 distally as it transects thetissue thickness compensator 14120 and, as a result, an even largerinternal pressure can be created within the distal end 14125 of thetissue thickness compensator 14120. In order to at least partiallydissipate this pressure within the tissue thickness compensator 14120,the nose 14103 can be comprised of a flexible material which can allowthe nose 14103 to flex distally, for example, and create additionalspace for the tissue thickness compensator 14120. In certainembodiments, referring now to FIGS. 362 and 363, the nose of a staplecartridge can comprise a portion which can slide distally. Moreparticularly, the nose 14203 of the staple cartridge 14200 can comprisea slidable portion 14204 which can be slidably connected to the nose14203 such that, when the anvil 10060 is closed and/or the firing member10052 is advanced into the distal end of the staple cartridge 14200, theslidable portion 14204 can slide distally and create additional room forthe tissue thickness compensator 14200 and at least partially alleviatethe internal pressure therein. In at least one embodiment, one of thenose 14203 and the slidable portion 14204 can comprise one or more railsand the other of the nose 14203 and the slidable portion 14204 cancomprise one or more channels configured to slidably receive the railstherein. In at least one such embodiment, the channels and rails can beconfigured to co-operatively limit the movement of the slidable portion14204 to a longitudinal distal path, for example.

In various circumstances, further to the above, certain staples, such asthe distal-most staples within a staple cartridge, for example, cancapture a larger portion of a tissue thickness compensator than theproximal staples within the staple cartridge. In such circumstances, asa result, a large clamping pressure can be applied to the tissuecaptured within the distal staples as compared to the proximal staples.These circumstances can arise when at least a portion of the tissuethickness compensator is shifted to and/or gathered at the distal end ofthe staple cartridge during use, as described above, eventhough thetissue thickness compensator may be comprised of a substantiallyhomogenous material having a substantially constant thickness. Invarious circumstances, it may be desirable for certain staples to applya higher clamping pressure to the tissue than other staples wherein, invarious embodiments, a support portion and/or a tissue thicknesscompensator can be constructed and arranged to control which staples mayapply the higher clamping pressure to the tissue and which staples mayapply a lower clamping pressure to the tissue. Referring now to FIG.364, a staple cartridge 14300 can comprise a support portion 14310 and,in addition, a tissue thickness compensator 14320 positioned on the decksurface 14311 of the support portion 14310. As compared to otherembodiments disclosed in this application which comprise a supportportion 14310 having a flat, or at least substantially flat, decksurface, the deck surface 14311 can be inclined and/or declined betweenthe distal end 14305 and the proximal end 14306 of the support portion14310. In at least one embodiment, the deck surface 14311 of the supportportion 14310 can comprise a deck height at its distal end 14305 whichis shorter than the deck height at its proximal end 14306. In at leastone such embodiment, the staples 10030 at the distal end of the staplecartridge 14300 can extend above the deck surface 14311 a largerdistance than the staples 10030 at the proximal end. In variousalternative embodiments, the deck surface of a support portion cancomprise a height at its distal end which is taller than its height atits proximal end. Referring again to FIG. 364, the tissue thicknesscompensator 14320 may comprise a thickness which is different along thelongitudinal length thereof. In various embodiments, the tissuethickness compensator 14320 can comprise a thickness at its distal end14325 which is thicker than its proximal end 14326, for example. In atleast one such embodiment, the tissue thickness compensator 14322 cancomprise a bottom surface 14322 which can be inclined or declined tomatch, or at least substantially match, the inclined or declined decksurface 14311 of the support portion 14310. As a result, the top, ortissue-contacting, surface 14321 of the tissue thickness compensator14320 can comprise a flat, or at least substantially flat, surface uponwhich the tissue T can be positioned. In any event, as the tissuethickness compensator 14320 is thicker at its distal end 14325, thedistal staples 10030 can capture a larger portion of the tissuethickness compensator 14320 therein than the proximal staples 10030 and,as a result, the distal staples 10030 can apply a larger compressiveforce to the tissue T, especially when the gap distance between theanvil 10060 and the deck surface 14311 is constant, or at leastsubstantially constant, at the proximal and distal ends of the staplecartridge. In certain circumstances, however, the anvil 10060 may notreach a fully closed position and, as a result, the gap distance betweenthe anvil 10060 and the deck surface 14311 may be larger at the distalend of the staple cartridge 14300 than the proximal end. In variouscircumstances, the distal staples 10030 may not be fully formed and, asa result, the distal staples 10030 may not apply the desired clampingpressure to the tissue T. In the embodiments where the tissue thicknesscompensator is thicker at the distal end of the staple cartridge, thetissue thickness compensator may compensate for the underforming of thestaples and apply a sufficient pressure to the tissue T.

In various embodiments, referring now to FIG. 365, a staple cartridge,such as staple cartridge 14400, for example, can comprise a supportportion 14410 and, in addition, a tissue thickness compensator 14420positioned on the deck surface 14411 of the support portion 14410.Similar to the above, the deck surface 14411 can be inclined and/ordeclined such that, in at least one embodiment, the distal end 14405 ofthe support portion 14410 can have a deck height which is shorter thanthe deck height at the proximal end 14406, for example. In certainembodiments, the tissue thickness compensator 14420 can comprise aconstant, or at least substantially constant, thickness along the lengththereof and, as a result, the top, or tissue-contacting, surface 14421of the tissue thickness compensator 14420 may parallel, or at leastsubstantially parallel, the contour of the deck surface 14411. Invarious embodiments, the staples 10030 of the staple cartridge 14400 canbe completely embedded within the tissue thickness compensator 14420 andthe support portion 14410 when the staples 10030 are in their unfiredposition. In certain embodiments, the staples 10030 positioned at theproximal end of the staple cartridge 14400 may be completely embeddedwithin the tissue thickness compensator 14420 and the support portion14410 when the staples 10030 are in their unfired position whereas, dueto the declined slope of the deck 14411 and top surface 14421, the tipsof certain staples 10030, including the staples 10030 positioned at thedistal end of the staple cartridge 14400, can protrude through the topsurface 14421 of the tissue thickness compensator 14420 when the staples10030 are in their unfired position.

In various embodiments, as described above, a tissue thicknesscompensator can be comprised of a single material wherein the entiretyof the tissue thickness compensator can have the same, or at leastsubstantially the same, material properties, such as density, stiffness,spring rate, durometer, and/or elasticity, for example, throughout. Invarious other embodiments, referring now to FIG. 368, a tissue thicknesscompensator, such as tissue thickness compensator 14520, for example,can comprise a plurality of materials or layers of materials. In atleast one embodiment, the tissue thickness compensator 14520 cancomprise a first, or central, layer 14520 a, second, or intermediate,layers 14520 b attached to the first layer 14520 a on opposite sidesthereof, and a third, or outer layer 14520 c attached to each of thesecond layers 14520 b. In certain embodiments, the intermediate layers14520 b can be attached to the central layer 14520 a utilizing at leastone adhesive and, similarly, the outer layers 14520 c can be attachedthe second layers 14520 utilizing at least one adhesive. In addition toor in lieu of an adhesive, the layers 14520 a-14520 c can be heldtogether by one or more interlocking features and/or fasteners, forexample. In any event, the inner layer 14520 a can be comprised of afirst material having a first set of material properties, theintermediate layers 14520 b can be comprised of a second material havinga second set of material properties, and the outer layers 14520 c can becomprised of a third material having a third set of material properties,for example. These sets of material properties can include density,stiffness, spring rate, durometer, and/or elasticity, for example. Incertain embodiments, a staple cartridge can comprise six rows of staples10030, for example, wherein a row of staples 10030 can be at leastpartially positioned in each of the outer layers 14520 c and each of theinner layers 14520 b, for example, and wherein two rows of staples 10030can be at least partially positioned with the inner layer 14520 a. Inuse, similar to the above, the staples 10030 can be ejected from thestaple cartridge such that the staple legs 10032 of the staples 10030penetrate the top surface 14521 of the tissue thickness compensator14520, penetrate tissue positioned against the top surface 14521 by ananvil, and then contact the anvil such that the legs 10032 are deformedto capture the tissue thickness compensator 14520 and the tissue withinthe staples 10030. Also similar to the above, the tissue thicknesscompensator 14520 can be transected by a firing member as the firingmember is advanced through the staple cartridge. In at least one suchembodiment, the firing member can transect the inner layer 14520 a, andthe tissue, along a path defined by axis 14529, for example.

In various embodiments, further to the above, the rows of staples 10030positioned within the inner layer 14520 a can comprise the staple rowswhich are closest to the edges of the transected tissue.Correspondingly, the rows of staples 10030 positioned within the outerlayers 14520 c can comprise the staple rows which are furthest away fromthe edges of the transected tissue. In certain embodiments, the firstmaterial comprising the inner layer 14520 a may comprise a density whichis higher than the density of the second material comprising theintermediate layers 14520 b and, similarly, the density of the secondmaterial may be higher than the density of the third material comprisingthe outer layers 14520 c, for example. In various circumstances, as aresult, larger compressive forces can be created within the staples10030 positioned within the inner layer 14520 a as compared to thecompressive forces generated within the staples 10030 positioned withinthe intermediate layers 14520 b and the outer layers 14520 c. Similarly,larger compressive forces can be created within the staples 10030positioned within the intermediate layers 14520 b as compared tocompressive forces created within the staples 10030 positioned withinthe outer layers 14520 c, for example. In various alternativeembodiments, the first material comprising the inner layer 14520 a maycomprise a density which is lower than the density of the secondmaterial comprising the intermediate layers 14520 b and, similarly, thedensity of the second material may be lower than the density of thethird material comprising the outer layers 14520 c, for example. Invarious circumstances, as a result, larger compressive forces can becreated within the staples 10030 positioned within the outer layers14520 c as compared to the compressive forces created within the staples10030 positioned within the intermediate layers 14520 b and the innerlayer 14520 a. Similarly, larger compressive forces can be createdwithin the staples 10030 positioned within the intermediate layers 14520b as compared to the compressive forces created within the staples 10030positioned within the inner layer 14520 a, for example. In various otherembodiments, any other suitable arrangement of layers, materials, and/ormaterial properties could be utilized. In any event, in variousembodiments, the layers 14520 a-14520 c of the tissue thicknesscompensator 14520 can be configured to remain attached to one anotherafter they have been implanted. In certain other embodiments, the layers14520 a-14520 c of the tissue thickness compensator 14520 can beconfigured to detach from one another after they have been implanted. Inat least one such embodiment, the layers 14520 a-14520 c can be bondedtogether utilizing one or more bioabsorbable adhesives which caninitially hold the layers together and then allow the layers to releasefrom one another over time.

As described above, a tissue thickness compensator of a staplecartridge, such as tissue thickness compensator 14520, for example, cancomprise a plurality of longitudinal layers. In various otherembodiments, referring now to FIG. 369, a staple cartridge can comprisea tissue thickness compensator, such as tissue thickness compensator14620, for example, which can comprise a plurality of horizontal layers.In at least one such embodiment, the tissue thickness compensator 14620can comprise a first, or bottom, layer 14620 a, a second, orintermediate, layer 14620 b attached to the bottom layer 14620 a, and athird, or top, layer 14620 c attached to the intermediate layer 14620 b.In various embodiments, the first layer 14620 a can comprise a flat, orsubstantially flat, bottom surface 14626 a and a triangular, orpyramidal, top surface 14625 a, for example. In at least one suchembodiment, the second layer 14620 b can comprise a triangular, orpyramidal, bottom surface 14626 b which can be configured to paralleland abut the top surface 14625 a of the first layer 14620 a. Similar tothe above, the second layer 14620 b can comprise a triangular, orpyramidal, top surface 14625 b which can parallel and abut a bottomtriangular, or pyramidal, bottom surface 14626 c of the third layer14620 c, for example. In various embodiments, the top surface of thethird layer 14626 c can comprise a flat, or at least substantially flat,tissue-contacting surface 14621. Also similar to the above, the tissuethickness compensator 14620 can be configured to at least partiallystore six rows of staples, such as staples 10030, for example, thereinwherein a firing member can transect the tissue thickness compensator14620 between the two innermost staple rows along a path extendingthrough axis 14629, for example. Similar to the above, each layer 14620a, 14620 b, and 14620 c can be comprised of a different material whichcan comprise different material properties and, as a result of thetriangular, or pyramidal, configuration of the layers 14620 a-14620 c,the tissue thickness compensator 14620 can have different overallproperties at various locations therewithin. For example, the outermostrows of staples 10030 may capture more of the third layer 14620 c thanthe first layer 14620 a therein whereas the innermost rows of staples10030 may capture less of the third layer 14620 c than the first layer14620 a and, as a result, the tissue thickness compensator 14620 maycompress the tissue captured within the outermost staples 10030differently than the tissue captured within the innermost staples 10030,for example, eventhough the tissue thickness compensator 14620 may havethe same, or at least substantially the same, overall thicknessthereacross.

In various embodiments, referring now to FIG. 286, a tissue thicknesscompensator of a staple cartridge, such as tissue thickness compensator14720 of staple cartridge 14700, for example, can comprise voids,pockets, channels, and/or grooves, for example, defined therein whichcan vary the thickness of the tissue thickness compensator 14720. In atleast one such embodiment, the tissue thickness compensator 14720 can bepositioned against the deck surface 14711 of a support portion 14710 ofthe staple cartridge 14700 such that voids 14723 defined in the bottomsurface 14722 of the tissue thickness compensator 14720 can overliecertain staple cavities 10012, but not others. In various embodiments,the voids 14723 can extend transversely to the knife slot 14715 of thesupport portion 14710, perpendicular to the knife slot 14715, and/orparallel to the knife slot 14715, for example. In certain embodiments,the voids 14723 can define a tread pattern in the bottom surface 14722of the tissue thickness compensator 14720. In any event, when staples,such as staples 10030, for example, are deployed from the supportportion 14710, referring now to FIGS. 287 and 288, certain staples 10030can capture the tissue thickness compensator 14720 within a regioncontaining a void 14723 while other staples 10030 can capture the tissuethickness compensator 14720 within a region positioned intermediate thevoids 14723. In addition to or in lieu of the above, the tissuethickness compensator 14720 can comprise voids, pockets, channels,and/or grooves, for example, defined in the top, or tissue-contacting,surface 14721. In certain embodiments, referring now to FIGS. 366 and367, a staple cartridge 14800 can comprise a tissue thicknesscompensator 14820 which can include a plurality of treads 14823extending at least one of upwardly from a top surface 14821 of thetissue thickness compensator 14820, inwardly toward a central groove14825, and/or distally toward the distal end of the staple cartridge14800, for example. In at least one such embodiment, the treads 14823can be separated by channels, slots, and/or grooves, such as channels14824, for example. In various circumstances, as a result of the above,the overall thickness of the tissue thickness compensator can varybetween staple rows and/or vary between the staples within a staple row.In certain circumstances, the treads, or thick portions, can beconstructed and arranged such that they can flow in a desire direction,such as inwardly, for example, when the tissue thickness compensator iscompressed.

In various embodiments, referring now to FIG. 303, a staple cartridge,such as staple cartridge 14900, for example, can comprise a supportportion 14910 and, in addition, a tissue thickness compensator 14920positioned against the support portion 14910. Similar to the above, thesupport portion 14910 can comprise staple drivers which can be liftedupwardly by a staple-deploying sled in order to lift staples, such asstaples 10030, for example, at least partially positioned within thesupport portion 14910 toward an anvil, such as anvil 10060, for example,positioned opposite the staple cartridge 14900. In certain embodiments,the support portion 14910 can comprise six rows of staple cavities, suchas two outer rows of staple cavities, two inner rows of staple cavities,and two intermediate rows of staple cavities positioned intermediate theinner rows and the outer rows, for example, wherein the anvil 10060 cancomprise six rows of forming pockets 10062 aligned, or at leastsubstantially aligned, with the staple cavities. In various embodiments,the inner rows of staple cavities can include staple drivers 14940 apositioned therein, the intermediate rows of staple cavities can includestaple drivers 14940 b positioned therein, and the outer rows of staplecavities can include staple drivers 14940 c positioned therein, whereineach of the staple drivers 14940 a can include a cradle 14949 aconfigured to support a staple 10030, wherein each of the staple drivers14940 b can include a cradle 14949 b configured to support a staple10030, and wherein each of the staple drivers 14940 c can include acradle 14949 c configured to support a staple 10030. In their unfiredpositions, i.e., when the staple drivers 14940 a-14940 c are sitting ondriver supports 14926 which extend underneath the support portion 14910,the cradles 14949 a of the staple drivers 14940 a can be positionedcloser to the anvil 10060 than the cradles 14949 b of the staple drivers14940 b and the cradles 14949 c of the staple drivers 14940 c. In such aposition, a first forming distance can be defined between the cradles14949 a and the forming pockets 10062 positioned over the cradles 14949a, a second forming distance can be defined between the cradles 14949 band the forming pockets 10062 positioned over the cradles 14949 b, and athird forming distance can be defined between the cradles 14949 c andthe forming pockets 10062 positioned over the cradles 14949 c, wherein,in various embodiments, the first forming distance can be shorter thanthe second forming distance and the second forming distance can beshorter than the third forming distance, for example. When the stapledrivers 14940 a-14940 c are moved from their unfired positions (FIG.303) to their fired positions, each staple driver 14940 a-14940 c can bemoved upwardly an equal, or an at least substantially equal, distancetoward the anvil 10060 by the staple-deploying sled such that the firstdrivers 14940 a drive their respective staples 10030 to a first formedheight, the second drivers 14940 b drive their respective staples 10030to a second formed height, and the third drivers 14940 c drive theirrespective staples 10030 to a third formed height, wherein the firstformed height can be shorter than the second formed height and thesecond formed height can be shorter than the third formed height, forexample. Various other embodiments are envisioned in which the firststaple drivers 14940 a are displaced upwardly a first distance, thesecond staple drivers 14940 b are displaced upwardly a second distance,and the third staple drivers 14940 c are displaced upwardly a thirddistance, wherein one or more of the first distance, the seconddistance, and the third distance can be different.

In various embodiments, referring again to FIG. 303, the deck surface14911 of the support portion 14910 can vary in height with respect tothe tissue-contacting surface 10061 of the anvil 10060. In certainembodiments, this height variation can occur laterally and, in at leastone embodiment, the height of the deck surface 14911 surrounding theinner rows of staple cavities can be higher than the deck surface 14911surrounding the outer rows of staple cavities, for example. In variousembodiments, the bottom surface 14922 of the tissue thicknesscompensator 14920 can be configured to parallel, or at leastsubstantially parallel, the deck surface 14911 of the support portion14910. Further to the above, the tissue thickness compensator 14920 canalso vary in thickness wherein, in at least one embodiment, the top, ortissue-contacting, surface 14921 of the tissue thickness compensator14920 can slope inwardly from the outside or lateral edges thereof. Inat least one such embodiment, as a result of the above, the tissuethickness compensator 14920 can be thinner in a region positioned overthe inner rows of staple cavities and thicker in a region positionedover the outer rows of staple cavities, for example. In variousembodiments, referring now to FIG. 304, the deck surface of a supportportion 15010 can comprise a stepped deck surface, for example, whereinthe highest steps of the stepped surface can surround the inner rows ofstaple cavities and the lowest steps of the stepped surface can surroundthe outer rows of staple cavities, for example. In at least one suchembodiment, steps having an intermediate height can surround theintermediate rows of staple cavities. In certain embodiments, a tissuethickness compensator, such as tissue thickness compensator 15020, forexample, can comprise a bottom surface which can parallel and abut thedeck surface of the support portion 15010. In at least one embodiment,the top, or tissue-contacting, surface 15021 of the tissue thicknesscompensator can comprise an arcuate, parabolic, and/or curved surface,for example, which, in at least one such embodiment, can extend from afirst lateral side of the tissue thickness compensator 15020 to a secondlateral side of the tissue thickness compensator 15020 with an apexaligned, or at least substantially aligned, with the center of thestaple cartridge 15000, for example. In various embodiments, referringnow to FIG. 299, a staple cartridge 15300, for example, can comprise asupport portion 15310, a plurality of staple drivers 15340 movablypositioned within staple cavities defined in the support portion 15310,and a tissue thickness compensator 15320 positioned above the decksurface 15311 of the support portion 15310. The staple cartridge 15300can further comprise one or more bottom pan portions 15326 which can beattached to the support portion 15310 and extend around the bottom ofthe support portion 15310 and support the drivers 15340, and staples15330, in their unfired positions. As a staple-deploying sled isadvanced through the staple cartridge, the sled can also be supported bythe bottom pan portions 15326 as the sled lifts the staple drivers 15340and the staples 15330 upwardly through the tissue thickness compensator15320. In at least one embodiment, the tissue thickness compensator15320 can comprise a first, or inner, portion 15322 a positioned over aninner row of staple cavities, a second, or intermediate portion 15322 bpositioned over an intermediate row of staple cavities, and a third, orouter, portion 15322 c positioned over a row of staple cavities, whereinthe inner portion 15322 a can be thicker than the intermediate portion15322 b and the intermediate portion 15322 b can be thicker than theouter portion 15322 c, for example. In at least one embodiment, thetissue thickness compensator 15320 can comprise longitudinal channels,for example, defined therein which can create the thinner portions 15322b and 15322 c of the tissue thickness compensator 15320. In variousalternative embodiments, the longitudinal channels can be defined in thetop surface and/or the bottom surface of a tissue thickness compensator.In at least one embodiment, the top surface 15321 of the tissuethickness compensator 15320 can comprise a flat, or at leastsubstantially flat, surface, for example.

In various embodiments, referring now to FIG. 296, a staple cartridgecan comprise a tissue thickness compensator, such as tissue thicknesscompensator 15120, for example, which can comprise a plurality ofportions having different thicknesses. In at least one embodiment, thetissue thickness compensator 15120 can comprise a first, or inner,portion 15122 a which can have a first thickness, second, orintermediate, portions 15122 b extending from the first portion 15122 bwhich can each have a second thickness, and third, or outer, portions15122 c extending from the second portions 15122 b which can each have athird thickness. In at least one such embodiment, the third thicknesscan be thicker than the second thickness and the second thickness can bethicker than the first thickness, for example, although any suitablethicknesses could be utilized in various other embodiments. In variousembodiments, the portions 15122 a-15122 c of the tissue thicknesscompensator 15120 can comprise steps having different thickness. In atleast one embodiment, similar to the above, a staple cartridge cancomprise several rows of staples 10030 and a plurality of staple drivershaving different heights which can deform the staples 10030 to differentformed heights. Also similar to the above, the staple cartridge cancomprise first staple drivers 15140 a which can drive the staples 10030supported thereon to a first formed height, second staple drivers 15140b which can drive the staples 10030 supported thereon to a second formedheight, and third staple drivers which can drive the staples 10030supported thereon to a third formed height, wherein the first formedheight can be shorter than the second formed height and the secondformed height can be shorter than the third formed height, for example.In various embodiments, as illustrated in FIG. 296, each staple 10030can comprise the same, or substantially the same, unformed, or unfired,height. In certain other embodiments, referring now to FIG. 296A, thefirst drivers 15140 a, the second drivers 15140 b, and/or the thirddrivers 15140 c can support staples having different unformed heights.In at least one such embodiment, the first staple drivers 15140 a cansupport staples 15130 a having a first unformed height, the secondstaple drivers 15140 b can support staples 15130 b having a secondunformed height, and the third staple drivers 15140 c can supportstaples 15130 c having a third unformed height, wherein the firstunformed height can be shorter than the second unformed height and thesecond unformed height can be shorter than the third unformed height,for example. In various embodiments, referring again to FIG. 296A, thetips of the staples 15130 a, 15130 b, and/or 15130 c can lie, or atleast substantially lie, in the same plane while, in other embodiments,the tips of the staples 15130 a, 15130 b, and/or 15130 c may not lie insame plane. In certain embodiments, referring now to FIG. 297, a staplecartridge can include a tissue thickness compensator 15220 having aplurality of portions having different thickness which can be implantedagainst the tissue T by the staples 15130 a, 15130 b, and 15130 c, asdescribed above. In at least one embodiment, referring now to FIG. 298,the staples 15130 a, 15130 b, and/or 15130 c can be deformed todifferent formed heights wherein the first staples 15130 a can be formedto a first formed height, the second staples 15130 b can be formed to asecond formed height, and the third staples 15130 c can be formed to athird formed height, and wherein the first formed height can be shorterthan the second formed height and the second formed height can beshorter than the third formed height, for example. Other embodiments areenvisioned in which the staples 15130 a, 15130 b, and 15130 c can beformed to any suitable formed heights and/or any relative formedheights.

In various embodiments, as described above, the anvil of a surgicalstapling instrument can be moved between an open position and a closedposition. In such circumstances, the tissue-contacting surface of theanvil can be moved into its final, or forming, position as the anvil ismoved into its closed position. Once the anvil is in its closedposition, in certain embodiments, the tissue-contacting surface may nolonger be adjustable. In certain other embodiments, referring now toFIG. 351, a surgical stapler, such as surgical stapler 15500, forexample, can comprise an anvil channel 15560 and an adjustabletissue-contacting anvil adjustment plate 15561 positioned within theanvil channel 15560. In such embodiments, the anvil plate 15561 can beraised and/or lowered within the anvil channel 15560 in order to adjustthe position of the tissue-contacting surface of the anvil plate 15561relative to a staple cartridge positioned opposite the anvil plate15561. In various embodiments, the surgical stapler 15500 can comprisean adjustment slide 15564 which, referring to FIGS. 356 and 357, can beslid intermediate the anvil channel 15560 and the anvil plate 15561 inorder to control the distance between the anvil plate 15561 and thestaple cartridge. In certain embodiments, referring again to FIGS. 351and 352, the surgical stapler 15500 can further comprise an actuator15562 coupled to the adjustment slide 15564 which can be slid proximallyin order to slide the adjustment slide 15564 proximally and/or sliddistally in order to slide the adjustment slide 15564 distally. Invarious embodiments, referring again to FIGS. 356 and 357, the actuator15562 can be slid between two or more pre-defined positions in order toadjust the anvil plate 15561 between two or more positions,respectively. In at least one embodiment, such pre-defined positions canbe demarcated on the surgical stapler 15500 as demarcations 15563 (FIG.351), for example. In certain embodiments, referring to FIG. 357, theadjustment slide 15564 can comprise a plurality of support surfaces,such as first support surface 15565 a, second support surface 15565 b,and third support surface 15565 c, for example, which can be alignedwith a plurality of plate positioning surfaces, such as firstpositioning surface 15569 a, second positioning surface 15569 b, andthird positioning surface 15569 c, respectively, on the backside of theanvil plate 15561 in order to position the anvil plate 15561 in a firstposition. In order to position the anvil plate 15561 in a secondposition, the actuator 15562 and the slide 15564 can be slid proximally,for example, in order to realign the support surfaces 15565 a-15565 c ofthe slide 15564 relative to the positioning surfaces 15569 a-15569 c ofthe anvil plate 15561. More particularly, referring to FIG. 356, theslide 15564 can be slid distally such that the first support surface15565 a of the slide 15564 can be positioned behind the secondpositioning surface 15569 b of the anvil plate 15561 and such that thesecond support surface 15565 b of the slide 15564 can be positionedbehind the third positioning surface 15569 c of the anvil plate 15561 inorder to move the anvil plate 15561 closer to the staple cartridge. Whenthe anvil plate 15561 is moved from its first position to its secondposition, in such circumstances, the adjustable anvil plate 15561 canfurther compress the tissue T positioned between the anvil plate 15561and the staple cartridge. In addition to the above, the formed height ofthe staples can be controlled by the position of the anvil plate 15561relative to the staple cartridge as the forming pockets defined in theanvil plate 15561 will move closer to and/or further away from thestaple cartridge when the anvil plate 15561 is adjusted. Although onlytwo positions are discussed above, the slide 15564 can be slid into asuitable number of positions to move the anvil plate 15561 closer toand/or away from the staple cartridge. In any event, once the anvilplate 15561 has been suitably positioned, a staple-deploying sled 15550can be slid distally within the staple cartridge in order to lift stapledrivers 15540 and staples 15530 toward the anvil plate 15561 and staplethe tissue T, as illustrated in FIG. 354. Similar surgical staplers aredisclosed in U.S. patent application Ser. No. 13/036,647, entitledSURGICAL STAPLING INSTRUMENT, which was filed on Feb. 28, 2011, theentire disclosure of which is incorporated by reference herein.

In various embodiments, referring now to FIG. 353, a staple cartridgecan be positioned within a staple cartridge channel 15570 of thesurgical stapler 15500 which can comprise a tissue thicknesscompensator, such as tissue thickness compensator 15520, for example.When the anvil plate 15561 is moved toward the staple cartridge, asdescribed above, the anvil plate 15561 can compress the tissue thicknesscompensator 15520 and/or the tissue T positioned intermediate the anvilplate 15561 and the tissue thickness compensator 15520. As the staples15530 are deployed from the staple cartridge, referring to FIG. 355, thestaples 15530 can compress and implant the tissue thickness compensator15520 against the tissue T. In various embodiments, when the anvil plate15561 is positioned against the slide 15564 and tissue has not yet beenplaced between the anvil plate 15561 and the tissue thicknesscompensator 15520, a gap can be defined between the anvil plate 15561and the top surface 15521 of the tissue thickness compensator 15520 whenthe anvil plate 15561 is in a first position. When the anvil plate 15561is moved into a second position, the anvil plate 15561 can contact thetissue thickness compensator 15520. In various alternative embodiments,when the anvil plate 15561 is positioned against the slide 15564 andtissue has not yet been placed between the anvil plate 15561 and thetissue thickness compensator 15520, a gap can be defined between theanvil plate 15561 and the top surface 15521 of the tissue thicknesscompensator 15520 when the anvil plate 15561 is in a first positionand/or a second position. In at least one such embodiment, the anvilplate 15561 may not come into contact with the tissue thicknesscompensator 15520. In further alternative embodiments, when the anvilplate 15561 is positioned against the slide 15564 and tissue has not yetbeen placed between the anvil plate 15561 and the tissue thicknesscompensator 15520, the anvil plate 15561 can be in contact with the topsurface 15521 of the tissue thickness compensator 15520 regardless ofwhether the anvil plate 15561 is in a first position and/or a secondposition, for example. Although only two positions for the anvil plate15611 are described herein, the anvil plate 15611 may be positioned, orindexed, into any suitable number of positions.

In various embodiments, as a result of the above, a surgical staplinginstrument can comprise means for adjusting the formed height of thestaples which can, in various circumstance, compensate for differenttissue thicknesses. In addition, the surgical stapling instrument cancomprise other means for compensating for different tissue thicknessesand/or thickness variations within the tissue, for example. In at leastone such embodiment, the anvil plate 15561 can be adjusted upwardly, oraway, from the opposing staple cartridge to increase the formed, orfired, height of the staples. Correspondingly, the anvil plate 15561 canbe adjusted downwardly, or toward, the opposing staple cartridge todecrease the formed, or fired, height of the staples. In variousembodiments, the adjustment of the anvil plate 15561, for example, canadjust the gap between the forming pockets defined in the anvil plate15561 and the fired height of the staple drivers or, more specifically,the fired height of the staple driver cradles, for example. Even withsuch a capacity to adjust the formed height of the staples to accountfor thicker and/or thinner tissue, for example, a tissue thicknesscompensator can also compensate for thicker and/or thinner tissue and/orcompensate for thickness variations within the tissue, as describedabove. In such embodiments, a surgeon can be afforded with severalcompensation means within the same surgical stapling instrument.

As described above and illustrated in several embodiments, a surgicalstapling instrument can utilize a staple cartridge having a lineararrangement of staple cavities and staples wherein a firing member canbe advanced distally through the staple cartridge to deploy the staplesfrom the staple cavities. In certain embodiments, a staple cartridge cancomprise rows of staple cavities and staples which are curved. In atleast one embodiment, referring now to FIGS. 345 and 346, a surgicalstapling instrument, such as stapler 15600, for example, can compriseone or more circular or annular rows of staple cavities defined in acircular or annular support portion 15610. Such circular staple rows cancomprise a circular row of inner staple cavities 15612 and a circularrow of outer staple cavities 15613, for example. In at least one suchembodiment, the circular rows of staple cavities can surround a circularor annular aperture 15615 defined in the stapler 15600 which can house acircular or annular knife movably positioned therein. In use, tissue canbe positioned against the deck surface 15611 of the support portion15610 and an anvil (not illustrated) can be assembled to the surgicalstapler 15600 via an actuator extending through and/or positioned withinthe aperture 15615 such that, when the actuator is actuated, the anvilcan be clamped toward the support portion 15610 and compress the tissueagainst the deck surface 15611. Once the tissue has been sufficientlycompressed, the staples positioned within the staple cavities 15612 and15613 can be ejected from the support portion 15610 and through thetissue such that the staples can contact the anvil and be sufficientlydeformed to capture the tissue therein. As the staples are being firedand/or after the staples have been fired, the circular knife can beadvanced to transect the tissue. Thereafter, the anvil can be moved awayfrom the support portion 15610 and/or detached from the surgical stapler15600 such that the anvil and the surgical stapler 15600 can be removedfrom the surgical site. Such surgical staplers 15600 and such surgicaltechniques, in various embodiments, can be utilized to join two portionsof a large intestine, for example. In various circumstances, thecircular staple lines may be configured to hold the portions of thelarge intestine together while the tissue heals and, at the same time,permit the portions of the large intestine to resiliently expand.Similar surgical stapling instruments and surgical techniques aredisclosed in U.S. Pat. No. 5,285,945, entitled SURGICAL ANASTOMOSISSTAPLING INSTRUMENT, which issued on Feb. 15, 1994, the entiredisclosure of which is incorporated by reference herein.

In various embodiments, further to the above, a tissue thicknesscompensator may be positioned against and/or attached to the supportportion 15610 of the surgical stapler 15600, for example. In at leastone embodiment, the tissue thickness compensator can be comprised of acircular or annular ring of material comprising an inner radius and anouter radius, for example. In certain circumstances, tissue can bepositioned against this ring of material and, when the anvil is used tomove the tissue toward the support portion 15610, the tissue thicknesscompensator can be compressed between the tissue and the deck surface15611. During use, the staples can be fired through the tissue thicknesscompensator and the tissue such that the staples can contact the anviland deform to their fired position to capture portions of the tissue andthe tissue thickness compensator within the staples. In variouscircumstances, further to the above, the ring of material comprising thetissue thickness compensator must be sufficiently resilient to permitthe portions of the large intestine surrounding the staple lines toexpand. In various embodiments, referring again to FIGS. 345 and 346, aflexible tissue thickness compensator 15620 can comprise a circular orannular flexible inner ring 15624, for example, which, in at least oneembodiment, can define a circular or annular aperture 15625. In certainembodiments, the inner ring 15624 may be configured such that it is notcaptured within staples deployed from the surgical stapler 15600;rather, in at least one embodiment, the inner ring 15624 may bepositioned radially inwardly with respect to the inner row of staplecavities 15612. In at least one such embodiment, the tissue thicknesscompensator 15620 can comprise a plurality of tags, such as inner tags15622 and outer tags 15623, for example, extending therefrom such thatthe tags can be at least partially captured within the staples as theyare being deformed. More particularly, referring primarily to FIG. 345,each inner tag 15622 can comprise a head which is positioned over astaple cavity 15612 defined in the surgical stapler 15600 wherein thehead can be attached to the inner ring 15624 by a neck 15626, forexample, and, similarly, each outer tag 15623 can comprise a head whichis positioned over a staple cavity 15613 defined in the surgical stapler15600 wherein the head can be attached to the inner ring 15624 by a neck15627, for example. In various embodiments, the heads of the inner tags15622 and the outer tags 15623 can comprise any suitable shape, such asround, oval, and/or elliptical, for example. The necks 15626 and/or15627 can also comprise any suitable shape wherein, in at least oneembodiment, the necks 15627 connecting the heads of the outer tags 15623to the inner ring 15624 can be configured to extend between adjacentinner staple cavities 15612 in the support portion 15610 such that thenecks 15627 are not captured within the staples deployed from the innerstaple cavities 15612.

In various embodiments, referring now to FIGS. 347 and 348, a flexibletissue thickness compensator 15720 can comprise a circular or annularflexible outer ring 15724, for example. In certain embodiments, theouter ring 15724 may be configured such that it is not captured withinstaples deployed from the surgical stapler 15600; rather, in at leastone embodiment, the outer ring 15724 may be positioned radiallyoutwardly with respect to the outer row of staple cavities 15613. In atleast one such embodiment, the tissue thickness compensator 15720 cancomprise a plurality of tags, such as inner tags 15622 and outer tags15623, for example, extending therefrom such that the tags can be atleast partially captured within the staples as they are being deformed.More particularly, referring primarily to FIG. 347, each inner tag 15622can comprise a head which is positioned over a staple cavity 15612defined in the surgical stapler 15600 wherein the head can be attachedto the outer ring 15724 by a neck 15726, for example, and, similarly,each outer tag 15623 can comprise a head which is positioned over astaple cavity 15613 defined in the surgical stapler 15600 wherein thehead can be attached to the outer ring 15724 by a neck 15727, forexample. In various embodiments, the heads of the inner tags 15622 andthe outer tags 15623 can comprise any suitable shape, such as round,oval, and/or elliptical, for example. The necks 15726 and/or 15727 canalso comprise any suitable shape wherein, in at least one embodiment,the necks 15726 connecting the heads of the inner tags 15622 to theouter ring 15724 can be configured to extend between adjacent outerstaple cavities 15613 such that the necks 15726 are not captured withinthe staples deployed from the outer staple cavities 15613. In certainalternative embodiments, a tissue thickness compensator can comprise acircular or annular flexible inner ring, a circular or annular flexibleouter ring, and, in addition, a plurality of tags which can be connectedto the inner ring and/or the outer ring. In at least one embodiment,certain tags can be connected to the inner ring and certain other tagscan be connected to the outer ring. In certain embodiments, at leastsome of the tags can be connected to both the inner ring and the outerring. In any event, further to the above, the inner ring 15624 of thetissue thickness compensator 15620, the outer ring 15724 of the tissuethickness compensator 15720, and/or any other suitable tissue thicknesscompensator, can be configured to resiliently expand and/or contract inorder to accommodate the expansion and/or contraction of the tissue thatit has been implanted against. Furthermore, although various embodimentsare described herein as comprising circular or annular support rings, atissue thickness compensator can comprise any suitably-shaped supportstructure for connecting the tags thereto. In various embodiments,further to the above, the circular knife advanced by the surgicalstapler to cut the tissue captured between the anvil and the supportportion can also cut the buttress material. In at least one suchembodiment, the knife can separate the inner support ring from the tagsby cutting the necks thereof, for example.

In various embodiments, further to the above, a tissue thicknesscompensator can comprise detachable and/or relatively movable positionswhich can be configured to allow the tissue thickness compensator toexpand and/or contract in order to accommodate the movement of thetissue that it has been implanted against. Referring now to FIGS. 349and 350, a circular or annular tissue thickness compensator 15820 can bepositioned against and/or supported by the deck surface 15611 of thesurgical stapler 15600 which can be held in an unexpanded position (FIG.349) as it is being implanted against the tissue and, after the tissuethickness compensator 15820 has been implanted, the tissue thicknesscompensator 15820 can be configured to expand outwardly, as illustratedin FIG. 350. In various embodiments, the tissue thickness compensator15820 can comprise a plurality of arcuate portions 15822 which can beconnected together by an inner ring 15824, for example. In at least oneembodiment, the arcuate portions 15822 can be separated from one anotherby seams 15828. In at least one other embodiment, the arcuate portions15822 may be connected to one another wherein, in at least one suchembodiment, an arrangement of perforations may permit the arcuateportions 15822 to separate from one another. In either event, in variousembodiments, the arcuate portions 15822 can each comprise interlockingfeatures, such as projections 15826 and notches 15823, for example,which can co-operate to limit relative movement between the arcuateportions 15822 prior to the tissue thickness compensator 15820 beingimplanted. Further to the above, each arcuate portion 15822 can beconnected to the inner ring 15824 by one or more connectors 15827, forexample, which can be configured to releasably hold the arcuate portions15822 in position. After the staples, such as staples 10030, forexample, stored within the support portion 15610 have been utilized toimplant the tissue thickness compensator 15620 against the tissue,referring primarily to FIG. 350, the connectors 15827 can detach fromthe inner ring 15824 and allow the tissue thickness compensator 15820 toat least partially expand to accommodate movement within the underlyingtissue. In various circumstances, all of the arcuate portions 15822 maydetach from the inner ring 15824 while, in other circumstances, onlysome of the arcuate portions 15822 may detach from the inner ring 15824.In certain alternative embodiments, the arcuate portions 15822 can beconnected by flexible sections which can permit the arcuate portions15822 to move relative to each other but not detach from one another. Inat least one such embodiment, the flexible sections may not receivestaples therein and can be configured to stretch and/or contract toaccommodate the relative movement of the arcuate portions 15822. In theembodiment illustrated in FIGS. 349 and 350, the tissue thicknesscompensator 15820 can comprise eight arcuate portions 15822, forexample. In certain other embodiments, a tissue thickness compensatorcan comprise any suitable number of arcuate portions, such as two ormore arcuate portions, for example.

Further to the above, a tissue thickness compensator 15620, 15720,and/or 15820, for example, can be configured to compensate for thickerand/or thinner tissue captured between the anvil and the support portion15610 of the surgical instrument 15600. In various embodiments, similarto the above, the formed, or fired, height of the staples can beadjusted by moving the anvil toward and/or away from the support portion15610. More particularly, the anvil can be moved closer to the supportportion 15610 to decrease the formed height of the staples while,correspondingly, the anvil can be moved further away from the supportportion 15610 to increase the formed height of the staples. In suchembodiments, as a result, a surgeon can adjust the anvil away from thesupport portion 15610 to account for thick tissue and toward the supportportion 15610 to account for thin tissue. In various othercircumstances, the surgeon may decide not to adjust the anvil at all andrely on the tissue thickness compensator to account for the thinnerand/or thicker tissue. In various embodiments, as a result, the surgicalinstrument 15600 can comprise at least two means for compensating fordifferent tissue thicknesses and/or variations in the tissue thickness.

In various embodiments, as described above, a tissue thicknesscompensator can be attached to a support portion of a staple cartridge.In certain embodiments, the bottom surface of the tissue thicknesscompensator can comprise one of a layer of hooks or a layer of loopswhile a deck surface on the support portion can comprise the other oneof the layer of hooks and the layer of loops. In at least one suchembodiment, the hooks and the loops can be configured to engage oneanother and releasably retain the tissue thickness compensator to thesupport portion. In various embodiments, each hook can comprise anenlarged head extending from a neck, for example. In certainembodiments, a plurality of pads comprising the loops, for example, canbe bonded to the bottom surface of the tissue thickness compensatorwhile a plurality of pads comprising the hooks can be bonded to the decksurface of the support portion. In at least one embodiment, the supportportion can comprise one or more apertures and/or recesses, for example,which can be configured to receive an insert therein comprising hooksand/or loops. In addition to or in lieu of the above, a tissue thicknesscompensator can be removably mounted to an anvil utilizing such hook andloop arrangements, for example. In various embodiments, the hooks andloops can comprise fibrous surfaces, for example.

In various embodiments, as described above, a staple cartridge cancomprise a support portion and a tissue thickness compensator attachedto the support portion. In certain embodiments, as also described above,the support portion can comprise a longitudinal slot configured toreceive a cutting member therein and the tissue thickness compensatorcan comprise a retention member that can be retained in the longitudinalslot. In at least one embodiment, referring now to FIG. 386, a staplecartridge 16000 can comprise a support portion 16010 including a decksurface 16011 and a longitudinal slot 16015. The staple cartridge 16000can further comprise a tissue thickness compensator 16020 positionedabove the deck surface 16011. In various embodiments, the tissuethickness compensator 16020 can include a longitudinal retention member16025 which extends downwardly into the longitudinal slot 16015. In atleast one such embodiment, the retention member 16025 can be pressedinto the slot 16015 such that the interaction between the retentionmember 16025 and the slot 16015 can resist relative movement between thesupport portion 16010 and the tissue thickness compensator 16020. Invarious embodiments, the body of the tissue thickness compensator 16020can be comprised of a first material and the retention member 16025 canbe comprised of a second, or different, material. In certainembodiments, the body of the tissue thickness compensator 16020 can becomprised of a material having a first durometer and the retentionmember 16025 can be comprised of a material having a second durometer,wherein the second durometer can be higher than the first durometer, forexample. In use, in at least one embodiment, the staples 10030 can bepushed upwardly by staple drivers 10040 such that the tips of thestaples 10030 can push through the body of the tissue thicknesscompensator 16020 and emerge from the tissue contacting surface 16021and capture at least a portion of the tissue thickness compensator 16020against the targeted tissue. In various embodiments, a cutting memberpassing through the slot 16015 can transect the retention member 16025as the staples 10030 are being deployed. Once the tissue thicknesscompensator 16020 has been implanted, in various embodiments, theretention member 16025 can be pulled out of the slot 16015. In certainother embodiments, the body of the tissue thickness compensator 16020can be configured to detach from the retention member 16025.

Referring now to FIGS. 387 and 389, a staple cartridge 17000 cancomprise a support portion 17010 including a deck surface 17011 and alongitudinal slot 17015. The staple cartridge 17000 can further comprisea tissue thickness compensator 17020 positioned above the deck surface17011. In various embodiments, the tissue thickness compensator 17020can include a longitudinal retention member 17025 which extendsdownwardly into the longitudinal slot 17015. In at least one suchembodiment, the retention member 17025 can be pressed into the slot17015 such that the interaction between the retention member 17025 andthe slot 17015 can resist relative movement between the support portion17010 and the tissue thickness compensator 17020. In variousembodiments, the retention member 17025 can extend through the entiretyof the tissue thickness compensator 17020 to the top surface 17021thereof wherein body portions 17024 of the tissue thickness compensator17020 can be attached to opposite sides of the retention member 17025.In at least one such embodiment, the retention member 17025 can also beconfigured to resist the lateral deflection, for example, of the tissuethickness compensator 17020. In various embodiments, the body portions17024 can be comprised of a first material and the retention member17025 can be comprised of a second, or different, material. In certainembodiments, the body portions 17024 can be comprised of a materialhaving a first durometer and the retention member 17025 can be comprisedof a material having a second durometer, wherein the second durometercan be higher than the first durometer, for example. In variousembodiments, further to the above, a cutting member passing through theslot 17015 can transect the retention member 17025 as the staples 10030are being deployed. Once the tissue thickness compensator 17020 has beenimplanted, in various embodiments, the retention member 17025 can bepulled out of the slot 17015. In certain other embodiments, the bodyportions 17024 can be configured to detach from the retention member17025.

Referring now to FIG. 388, a staple cartridge 18000 can comprise asupport portion 18010 including a deck surface 18011 and a longitudinalslot 18015. The staple cartridge 18000 can further comprise a tissuethickness compensator 18020 positioned above the deck surface 18011. Invarious embodiments, the tissue thickness compensator 18020 can includea longitudinal retention member 18025 which extends downwardly into thelongitudinal slot 18015. In at least one such embodiment, the retentionmember 18025 can be pressed into the slot 18015 such that theinteraction between the retention member 18025 and the slot 18015 canresist relative movement between the support portion 18010 and thetissue thickness compensator 18020. In various embodiments, theretention member 18025 can extend through the entirety of the tissuethickness compensator 18020 to the top surface 18021 thereof whereinbody portions 18024 of the tissue thickness compensator 18020 can beattached to opposite sides of the retention member 18025. In at leastone embodiment, the retention member 18025 can comprise an enlargedportion 18026 which can be received in a cavity 18016 defined in theslot 18015. In at least one such embodiment, the enlarged portion 18026can resist the withdrawal of the retention member 18025 from the slot18015.

In various embodiments, friction can exist between a staple and a tissuethickness compensator. For example, high friction conditions can existbetween the legs of a staple and a tissue thickness compensator. Thehigh friction conditions can include a high sliding friction between thestaples and the tissue thickness compensator, for example. In certainembodiments, the high friction conditions can affect the firing and/orpuncturing force required to move the staples through the tissuethickness compensator during deployment, for example. In variousembodiments, high friction conditions can limit and/or prevent there-expansion and/or spring back of the tissue thickness compensatorwithin a staple entrapment area of a formed staple.

Referring now to the illustrative schematics in FIGS. 390 and 391, iflow friction, or possibly friction-less, conditions existed between thelegs 20132 of a staple 20130 and a tissue thickness compensator 20120,the tissue thickness compensator 20120 may not grip the legs 20132 ofthe staple 20130 during deployment through the tissue thicknesscompensator 20120. Furthermore, the tissue thickness compensator 20120may not remain in a frictionally deformed state, i.e., held to thestaple legs 20132 by frictional forces, after deployment of the staple20130 into tissue T. As a result, the tissue thickness compensator 20120can more effectively reform and/or re-expand within the stapleentrapment area 20139 to consume any unconsumed space, i.e., space notconsumed by tissue T, for example.

In various embodiments, it may be preferable to prevent and/or limitfrictional forces between a tissue thickness compensator and a staple.Referring now to FIGS. 392-395, a tissue thickness compensator 20220 foruse with a staple cartridge assembly 20200 can include a plurality ofclearance apertures 20224 extending at least partially through thetissue thickness compensator 20220. In various embodiments, the staplecartridge assembly 20200 can include a staple cartridge body 20210 and atissue thickness compensator 20220 releasably secured relative to thestaple cartridge body 20210. The cartridge body 20210 can include acartridge deck 20211 and a plurality of staple cavities 20212 definedthrough the cartridge deck 20211 and into the body of the staplecartridge body 20210, for example. Staples 20230 (FIGS. 394 and 395) canbe removably positioned in the staple cavities 20212, for example. Invarious embodiments, the tissue thickness compensator 20220 can includea tissue-contacting surface 20221 (FIG. 394) and a deck-contactingsurface 20222 (FIG. 393). The deck-contacting surface 20222 can bereleasably positioned against the deck 20211 of the cartridge body20210, for example, and the tissue-contacting surface 20221 can bepositioned against tissue T to be stapled, for example. In variousembodiments, the clearance apertures 20224 can extend through thedeck-contacting surface 20222 and into the tissue thickness compensator20220. In certain embodiments, referring primarily to FIG. 392,clearance apertures or through holes 20224′ of a tissue thicknesscompensator 20220′ can extend between a deck-contacting surface and atissue-contacting surface 20221′. For example, the clearance apertures20224′ can extend entirely through the tissue thickness compensator20220′. In other embodiments, referring primarily to FIGS. 393-395, theclearance apertures 20224 can extend only partially through the tissuethickness compensator 20220, for example. In various embodiments, theclearance apertures 20224 can comprise holes, slits, gaps, bores,openings, and/or cleared pathways, for example, within the tissuethickness compensator 20220.

Referring primarily to FIGS. 394 and 395, staples 20230 can bepositioned in the staple cavities 20212 of the cartridge body 20210.Each staple 20230 can include a base 20231 and a pair of staple legs20232, for example, which can extend from the base 20231. In variousembodiments, each staple leg 20232 can extend from opposite ends of thebase 20231. Referring primarily to FIG. 394, the clearance apertures20224 in the tissue thickness compensator 20220 can include an openingin the deck-contacting surface 20222. In various embodiments, theopening of a clearance aperture 20224 can be aligned with acorresponding staple leg 20232 that is positioned in a staple cavity20212. For example, a single staple leg 20232 can be aligned with theopening of a single clearance aperture 20224 when the tissue thicknesscompensator 20220 is secured relative to the cartridge body 20210. Incertain embodiments, a staple leg 20232 can extend into each clearanceaperture 20224, such that at least a portion of the staple 20230 isembedded in the tissue thickness compensator 20220, for example. Forexample, referring primarily to FIG. 394, a staple 20230 can include afirst staple leg 20232 a and a second staple leg 20232 b. Furthermore,the tissue thickness compensator 20220 can include a first clearanceaperture 20224 a aligned with the first staple leg 20232 a, and a secondclearance aperture 20224 b aligned with the second staple leg 20232 b,for example. Prior to deployment of the staple 20230, the first stapleleg 20232 a can extend partially through the first clearance aperture20224 a, and the second staple leg 20232 b can extend partially throughthe second clearance aperture 20224 b, for example. In variousembodiments, the tissue thickness compensator 20220 can includeadditional clearance apertures 20224 that are not aligned with staplelegs 20232, for example. In certain embodiments, the staple cartridgeassembly 20200 can include additional staples 20230 and/or staple legs20232 that are not aligned with clearance apertures 20224, for example.

In various embodiments, the staples 20230 can be moveable from anunfired configuration (FIG. 394) to a fired configuration (FIG. 395).Each staple 20230 can move along a staple axis when moving between theunfired configuration and the fired configuration. When in the unfiredconfiguration, the staple legs 20232 can extend from the staple cavities20212 and into the tissue thickness compensator 20220, for example. Thestaple legs 20232 can be partially embedded in the tissue thicknesscompensator 20220 when the staples 20230 are in the unfiredconfiguration, for example. Furthermore, at least a portion of thestaple legs 20232 can be aligned with and/or positioned within theclearance apertures 20224 of the tissue thickness compensator 20220 whenthe staples are in the unfired configuration, for example. In otherembodiments, the staple legs 20232 can be positioned entirely within thestaple cavity 20212 when in the unfired configuration, and can bealigned with the clearance apertures 20224 positioned above thecartridge deck 20211 (FIG. 393), for example.

In various embodiments, the staples 20230 can move from the unfiredconfiguration (FIG. 394) to the fired configuration (FIG. 395) during afiring stroke, as described herein. In certain embodiments, a stapledriver 20240 can be positioned within each staple cavity 20212. Thestaple driver 20240 within each staple cavity 20212 can be pushed towardthe cartridge deck 20211 (FIG. 393), for example, to drive the staple20230 into tissue T and toward an anvil 20260 (FIG. 395) of the surgicalend effector. As each staple 20230 moves from the unfired configurationto the fired configuration, the staple legs 20232 can move through theclearance apertures 20224 in the tissue thickness compensator 20220. Invarious embodiments, the clearance apertures 20224 can have a predefinedtrajectory within the tissue thickness compensator 20220. For example,the clearance apertures 20224 can extend along an axis that isperpendicular to and/or substantially perpendicular to thetissue-contacting surface 20221 (FIG. 394) and/or the deck-contactingsurface 20222 (FIG. 393) of the tissue thickness compensator 20220. Inother embodiments, the clearance apertures 20224 can extend along anaxis that is oriented at an oblique angle relative to thetissue-contacting surface 20221 and/or the deck-contacting surface 20222of the tissue thickness compensator 20220, for example. In certainembodiments, a group of the clearance apertures 20224 can be parallel.In some embodiments, all of the clearance apertures 20224 within thetissue thickness compensator 20220 can be parallel, for example. Invarious embodiments, the clearance apertures 20224 can comprise apartially curved trajectory and/or a partially linear trajectory. Incertain embodiments, the clearance apertures 20224 in the tissuethickness compensator 20220 can be laser cut into the tissue thicknesscompensator. In other embodiments, the clearance apertures 20224 can beformed with the tissue thickness compensator 20220 in a mold (notshown). For example, pins can extend into a cavity of the mold to formthe clearance apertures 20224.

Referring primarily to FIG. 394, the staple legs 20232 can have apredefined trajectory and/or orientation. In various embodiments, thetrajectory and/or orientation of the staple legs 20232 can be controlledby the geometry and/or dimensions of the staple 20230 itself and/or bythe geometry and/or dimensions of the staple cavity 20212. For example,as described herein, the staple cavities 20212 can include guidingand/or biasing features, which can bias the staple legs 20232 in apredefined orientation and/or can guide the staple legs 20232 along apredefined trajectory through the tissue thickness compensator 20220and/or into tissue T during the staple's deployment. For example,referring still to FIG. 394, the staple legs 20232 can be orientedperpendicular and/or substantially perpendicular to the staple base20231 and/or to the deck 20211 (FIG. 393) of the staple cartridge body20210, for example. In such embodiments, the staple legs 20232 can beoriented parallel and/or substantially parallel to the staple axis alongwhich the staple 20230 is fired during the staple's deployment. In otherembodiments, the staple legs 20232 can be angularly oriented relative tothe staple base 20231 and/or to the deck 20211. For example, the staplelegs 20232 can splay outward from the staple base 20231. In variousembodiments, the predefined trajectory of the clearance apertures 20224in the tissue thickness compensator 20220 can match the predefinedtrajectory of the staple legs 20232. For example, a staple leg 20232 anda clearance aperture 20224 can extend along the same axis. For example,where the staple legs 20232 are oriented perpendicular to the deck 20211(FIG. 394), the clearance apertures 20224 can be oriented perpendicularto the deck-contacting surface 20222 of the tissue thickness compensator20220 and can be aligned with the staple legs 20232.

In various embodiments, the clearance apertures 20224 can be sized toreceive the staple legs 20232. For example, each clearance aperture20224 can be sized to receive a single staple leg 20232. In variousembodiments, a clearance aperture 20224 can provide a clearance and/or agap between at least a portion of a staple leg 20232 and at least aportion of the tissue thickness compensator 20220. For example, at leasta portion of a clearance aperture 20224 can be wider than at least aportion of a corresponding staple leg 20232 and/or longer than at leasta portion of the corresponding staple leg 20232. For example, a stapleleg 20232 can define a maximum leg diameter, and a correspondingclearance aperture 20224 can define a minimum diameter that is greaterthan the maximum leg diameter. Further, a staple leg 20232 can define aleg length between the base 20231 and the tip of the staple leg 20232,and a corresponding clearance aperture 20224 can define a length withinthe tissue thickness compensator 20220 that results in a gap or spaceabove the tip of the staple leg 20232 when the staple 22030 is in anunfired configuration, for example. In various embodiments, a clearanceaperture 20224 can be one of wider or longer than a corresponding stapleleg 20232, for example, and, in other embodiments, a clearance aperture20224 can be both wider and longer than a corresponding staple leg20232, for example.

In various embodiments, the clearance apertures 20224 can eliminateand/or reduce the frictional forces between the tissue thicknesscompensator 20220 and the staple legs 20232. For example, the clearanceand/or gap defined between the staple legs 20232 and the tissuethickness compensator 20220, which is at least partially provided by theclearance apertures 20224, can limit and/or prevent contact between thestaple legs 20232 and the tissue thickness compensator 20220 as thestaple legs 20232 move through the tissue thickness compensator 20220and/or when the staple 20230 has captured tissue and the tissuethickness compensator 20220 within the staple entrapment area 20239(FIG. 395). In various embodiments, the reduced contact between thestaple legs 20232 and the tissue thickness compensator 20220 can resultin a corresponding reduction in frictional forces therebetween.Furthermore, in various embodiments, the clearance apertures 20224 canreduce and/or limit the firing and/or puncturing force necessary todrive the staples 20230 through the tissue thickness compensator 20220.In certain embodiments, the reduced friction between the tissuethickness compensator 20220 and the staples 20230 can allow the tissuethickness compensator 20220 to more effectively re-expand, reform,and/or spring back within the staple entrapment area 20239, for example,such that the tissue thickness compensator 20220 consumes space withinthe staple entrapment area 20239 that is not consumed by tissue T.

In various embodiments, staples for use with a staple cartridge assemblycan be “V”-shaped and/or “U”-shaped, for example. Further, the staplescan be sufficiently flexible, for example, such that the staples can bedeformed when in a stressed state. “V”-shaped staples can comprise abase and staple legs that splay outward from the base. In variousembodiments, a staple cavity in cartridge body of a staple cartridgeassembly can hold “V”-shaped staples in a modified “V”-shape. Forexample, a staple cavity may exert a compressive, holding force on a“V”-shaped staple to form a modified “V”-shaped. In various embodiments,the holding force exerted on the staple legs can secure the staple inthe staple cavity prior to ejection of the staple by a firing assemblyduring a firing stroke, as described herein. In certain embodiments, thestaple legs can remain at least slightly splayed outward when the“V”-shaped staple is held in the staple cavity by the compressive,holding force. The outward splay of the staple legs can define thetrajectory of the staple legs through a tissue thickness compensatorand/or into tissue, for example. In other words, the staple legs canpierce through the tissue thickness compensator and/or tissue at anoblique angle relative to the deck of the staple cartridge body and/orthe deck-contacting surface of the tissue thickness compensator, forexample. In other embodiments, a staple cavity can exert a compressive,holding force on a “V”-shaped staple to form a substantially “U” shapedstaple. In such embodiments, the staple legs can be flexed into aparallel or substantially parallel alignment, for example. In suchembodiments, the staple legs can pierce through the tissue thicknesscompensator and/or tissue at a right angle relative to the deck of thestaple cartridge body and/or the deck-contacting surface of the tissuethickness compensator, for example.

In certain embodiments, a guide or trajectory control can support thestaple legs and/or can guide the trajectory of the staple legs duringfiring. For example, referring now to FIGS. 396-399, a staple cartridgeassembly 20500 can include a cartridge body 20510 that comprises aplurality of guides 20514. In various embodiments, staples 20530 can bepositioned in the staple cavities 20512 of the cartridge body 20512. Thestaples 20530 can include a base 20531 and a pair of staple legs 20532,for example. In various embodiments, the staple legs 20532 can extendfrom opposite ends of the staple base 20531. The guides 20514 of thecartridge body 20510 can be positioned on either end of the staplecavities 20512. For example, a proximal guide 20514 b can be positionedat and/or near a proximal end of the staple cavity 20512, and a distalguide 20514 a can be positioned at and/or near a distal end of thestaple cavity 20512. The proximal guide 20514 b can guide a proximalstaple leg 20532 b, and the distal guide 20514 a can guide a distalstaple leg 20532 a, for example.

In various embodiments, the guides 20514 can comprise ridges,protrusions, bumps, extensions, pinchers and/or arms, for example. Theguides 20514 can extend inwardly of the first end and the second end ofthe staple cavity 20512, for example. For example, the guides 20514 canextend inwardly toward a central axis between the proximal end and thedistal end of the staple cavity 20512. Further, in certain embodiments,the guides 20514 can comprise a groove, notch, and/or channel, forexample, which can receive and/or slidably engage at least a portion ofthe staple leg 20532. The guides 20514 can extend inwardly from thecartridge body 20510, from the deck 20511 of the cartridge body 20510,and/or from an inner wall of the staple cavity 20512, for example. Invarious embodiments, the guides 20514 can be positioned above and/orbelow the deck 20511 (FIG. 396) of the cartridge body 20510. Forexample, referring primarily to FIG. 396, the proximal guide 20514 b andthe distal guide 20514 a can be positioned above the deck 20511.Referring still primarily to FIG. 396, the guides 20514 can comprise aninward taper 20518, for example, which can provide a localized contactregion for the staple leg 20532. In certain embodiments, the localizedcontact region can hold, guide, and/or bias the staple leg 20532 beforeand/or during firing of the staple 20530 from the staple cavity 20512,for example.

In various embodiments, the staple cavity 20512 can define a cavitywidth between a proximal end of the staple cavity 20512 and a distal endof the staple cavity 20512, for example. Furthermore, in variousembodiments, the guides 20514 can define a narrowed width between theproximal guide 20514 b and the distal guide 20514 a, for example. Inother words, the guides 20514 can define a narrower width than thestaple cavity 20512, for example. In such embodiments, the guides 20514can flex and/or bias the staple legs 20532 inward and away from thestaple cavity 20512 walls, for example. A gap or space can be definedbetween the staple legs 20532 and the staple cavity 20512 walls, forexample. In various embodiments, the staple cavity 20512 wall may onlystress the staples 20530 into modified “V”-shape, for example, however,the guides 20514 can stress the staples 20530 into a substantial“U”-shape, for example.

Referring primarily to FIGS. 397-399, the guides 20514 can flex and/orbias the staple legs 20532 toward a parallel and/or substantiallyparallel alignment. For example, the guides 20514 can bias and/or flexthe staple legs 20532 perpendicular and/or substantially perpendicularto the staple base 20531. Furthermore, the guides 20514 can bias and/orflex the staple legs 20532 parallel to the staple axis, along which thestaple 20530 moves during deployment, for example. In variousembodiments, the guides 20514 can hold the staple 20530 in a stressedstate before and/or throughout at least a portion of the staple'sdeployment. In other words, the guides 20514 can provide prolongedand/or extended inward biasing of the staple legs 20532, for example. Incertain embodiments, the staple legs 20532 can be held parallel when thestaple 20530 is unfired (FIG. 397) and partially fired (FIG. 398). Forexample, the staple legs 20532 near the base 20531 can remain parallelas the tips of the staple legs 20532 contact the anvil 20560 (FIGS. 398and 399) and begin to deform. Referring primarily to FIG. 398, theguides 20514, can continue to guide the staple legs 20532 as the tips ofthe staple legs 20532 engage the anvil 20560 and move toward a “B”-form,for example. Furthermore, the guides 20514 can continue to bias thestaple legs 20532 into parallel alignment until the staple legs 20532are ejected from the staple cavity 20512 and the staple 20530 has beencompletely formed by the anvil 20560 (FIG. 399), as described herein.

In certain embodiments, the guides 20514 can resist staple leg 20532splay throughout the staple's deployment. The guides 20514 can maintainthe parallel alignment of the staple legs 20532, for example. In otherembodiments, the guides 20514 can maintain a predefined, non-parallelorientation of the staple legs 20532. The tissue thickness compensator20520 can include clearance apertures 20524, similar to the clearanceapertures 20224 described herein, which can receive the staple legs20532, for example. In various embodiments, the guides 20514 canmaintain the staple legs 20532 in an orientation that matches thetrajectory of the clearance apertures 20524 throughout the staple'sdeployment, for example. In such embodiments, the guides 20514 of thestaple cartridge body 20510 can cooperate with the clearance apertures20524 of the tissue thickness compensator 20520 to reduce and/oreliminate frictional forces between the staple legs 20532 and the tissuethickness compensator 20520, for example.

In various embodiments, the guides 20514 can control the formation ofthe staples 20530 as the staples 20530 move from the unfiredconfiguration to the fired configuration. As a result, the staples 20530can be formed into a tighter and/or more compactly formed staple 20530,for example. A “B”-form can be more compact, for example, such that thestaple legs 20532 are more closely nested, intertwined, and/or movedcloser toward the base 20531, for example. Furthermore, in variousembodiments, the guides 20514 can restrain the staples 20530 duringdeployment, which can reduce tissue flow. For example, the predefinedtrajectory of the staple legs 20532 through the tissue T and tissuethickness compensator 20520 can be controlled to reduce lateral shiftingand/or flow of the tissue T. Various guides are disclosed in U.S. PatentApplication Publication No. 2012/0074198. The entire disclosure of U.S.patent application Ser. No. 12/893,461, entitled STAPLE CARTRIDGE, filedon Sep. 29, 2010, now U.S. Patent Application Publication No.2012/0074198, is hereby incorporated by reference herein. Moreover,while “B”-formed staples may be suitable in various circumstances, otherformed configurations may be suitable, such as those disclosed in U.S.Patent Application Publication No. 2011/0226837, for example. The entiredisclosure of U.S. patent application Ser. No. 13/036,647, entitledSURGICAL STAPLING INSTRUMENT, filed on Feb. 28, 2011, now U.S. PatentApplication Publication No. 2011/0226837, is hereby incorporated byreference herein.

Referring now to FIGS. 400-402, a staple cartridge assembly 20600 caninclude a cartridge body 20610 that comprises a plurality of guides20614, similar to the guides 20514, for example. The guides 20614 can bepositioned below the cartridge deck, for example, and can extend fromthe inner walls of the staple cavities 20612, for example. In variousembodiments, the staples 20630 can be positioned in the staple cavities20612 of the cartridge body 20612. The staples 20630 can include a base20631 and a pair of staple legs 20632 extending from the base 20631, forexample. The guides 20614 of the cartridge body 20610 can be positionedon either end of the staple cavities 20612. For example, a proximalguide 20614 b can be positioned at and/or near a proximal end of thestaple cavity 20612, and a distal guide 20614 a can be positioned atand/or near a distal end of the staple cavity 20612. The proximal guide20614 b can guide a proximal staple leg 20632 b, and the distal guide20614 a can guide a distal staple leg 20632 a, for example. Similar tothe guides 20514, the guides 20614 can extend inwardly, and can biasand/or flex the staple legs 20532 inward and/or away from the walls ofthe staple cavity 20612, for example.

Referring still to FIGS. 400-402, the guides 20614 can bias the staplelegs 20632 toward and/or into a parallel alignment, for example.Further, the guides 20614 can bias the staple legs 20632 such that theorientation and/or trajectory of the staple legs 20632 matches thetrajectory of the corresponding clearance apertures 20624 defined in thetissue thickness compensator 20620, for example. Furthermore, the guides20614 can bias and/or flex the staple legs 20632 parallel to the stapleaxis, along which the staple 20630 can move during deployment, forexample. In various embodiments, the guides 20614 can hold the staple20630 in the stressed state before and throughout at least a portion ofthe staple's deployment. In other words, the guides 20614 can provideprolonged and/or extended inward biasing of the staple legs 20632, forexample. In certain embodiments, the staple legs 20632 can be heldparallel by the guides 20614 when the staple 20630 is unfired (FIG.400). The guides 20614 can release the staple legs 20632 duringdeployment, and can release the staple legs 20632 before the tips of thestaple legs 20632 engage the anvil 20660 (FIG. 401), for example. Inother embodiments, the staple legs 20632 can engage the anvil before theguides 20614 release the staple 20630, for example, which may preventtemporary outward splay of the staple legs 20632, for example.

Referring now to FIGS. 403-405, a staple cartridge assembly 20700 caninclude a cartridge body 20710 that comprises a plurality of lowerguides 20714 and a plurality of upper guides 20716, which can be similarto the guides 20614 and 20514, respectively, for example. The lowerguides 20714 can be positioned below the cartridge deck, for example,and can extend from the inner walls of the staple cavities 20712, forexample. The upper guides 20716 can be positioned above and/or canextend from the cartridge deck, for example. In various embodiments,staples 20730 can be positioned in the staple cavities 20712 of thecartridge body 20712. The staples 20730 can include a base 20731 and apair of staple legs 20732 extending from the base 20731, for example.The guides 20714 and 20716 of the cartridge body 20710 can be positionedon either end of the staple cavities 20712. For example, proximal lowerand upper guides 20714 b and 20716 b, respectively, can be positioned atand/or near a proximal end of the staple cavity 20712, and distal lowerand upper guides 20714 a and 20716 a, respectively, can be positioned atand/or near a distal end of the staple cavity 20712. The proximal guides20714 b and 20716 b can guide a proximal staple leg 20732 b, and thedistal guides 20714 a and 20716 a can guide a distal staple leg 20732 a,for example. Similar to the guides 20514 and/or 20614, for example, theguides 20714 and 20716 can extend inwardly, and can bias and/or flex thestaple legs 20732 inward and/or away from the walls of the staple cavity20712, for example. In various embodiments, the lower guides 20714 andthe upper guides 20716 can cooperate to guide the staples 20730. Forexample, the lower guides 20714 can guide the staples 20730 during aportion of the staple's deployment, and the upper guides 20716 can guidethe staples 20730 during a similar, different, and/or overlappingportion of the staple's deployment, for example. The cooperating guides20714 and 20716 can further prevent skewing and/or torquing of thestaple 20730 during deployment, for example.

Referring still to FIGS. 403-405, the guides 20714 and 20716 can biasthe staple legs 20732 toward and/or into a parallel alignment, forexample. Further, the guides 20714 and 20716 can bias the staple legs20732 such that the orientation and/or trajectory of the staple legs20732 matches the trajectory of corresponding clearance apertures 20724defined in the tissue thickness compensator 20720, for example.Furthermore, the guides 20714 and 20716 can bias and/or flex the staplelegs 20732 parallel to the staple axis, along which the staple 20730 canmove during deployment, for example. In various embodiments, the guides20714 and 20716 can hold the staple 20730 in a stressed state before andthroughout at least a portion of the staple's deployment. In otherwords, the guides 20714 and 20716 can provide prolonged and/or extendedinward biasing of the staple legs 20732, for example. In certainembodiments, the staple legs 20732 can be held parallel by the upper andlower guides 20714 and 20716 when the staple 20730 is unfired (FIG.403). The lower guides 20714 can release the staple legs 20732 duringthe staple's deployment and the upper guides 20716 can maintain contactwith the staple legs 20732 throughout the staple's deployment (FIG.404). Referring primarily to FIG. 405, the upper guides 20716 canrelease the staple legs 20732 after the staple has been formed into asubstantial “B”-form, for example.

Referring now to FIGS. 406-409, an end effector of a surgical fasteninginstrument, such as end effector 22090, for example, can comprise afirst jaw including a fastener cartridge assembly 22000 and a second jawincluding an anvil 10060. The first jaw can include a staple cartridgechannel 10070 which can be configured to removably receive the cartridgeassembly 22000. Alternatively, the staple cartridge channel 10070 andthe cartridge assembly 22000 can comprise an integral unit. In variouscircumstances, the anvil 10060 can be moved between an open position anda closed position (FIGS. 406-409). In the open position of the anvil10060, the anvil 10060 can be positioned on a first side of a patient'stissue T (FIGS. 407-409) and the cartridge assembly 22000 can bepositioned on a second, or opposite, side of the tissue T, for example.When the anvil 10060 is moved into its closed position, as discussed ingreater detail further below, the anvil 10060 can compress the tissue Tagainst the cartridge assembly 22000. Alternatively, with reference toFIG. 395, discussed above, the first jaw including the cartridgeassembly 22000 can be moved relative to the anvil 10060. In eitherevent, the end effector 22090 can be closed by a closure drive of asurgical fastening instrument, as discussed above. Alternatively, theend effector 22090 can be closed by a firing member, such as firingmember 10052, for example, when the firing member 10052 is advanceddistally from a proximal end 22001 of the cartridge assembly 22000toward a distal end 22002 of the cartridge assembly 22000. Whether ornot the firing member 10052 is utilized to close the end effector 22090,the firing member 10052 can be configured to eject fasteners, such asstaples 22030, for example, removably stored in a cartridge body 22010of the cartridge assembly 22000 as the cutting member 10052 is advancedfrom the proximal end 22001 toward the distal end 22002 of the cartridgeassembly 22000.

Further to the above, the staples 22030 can be supported by stapledrivers 10040 which are movably positioned within staple cavities 22012defined in the cartridge body 22010. Moreover, the firing member 10052can be configured to advance a staple-firing sled 10050 distally withinthe cartridge body 22010 as the firing member 10052 is moved from theproximal end 22001 toward the distal end 22002. In such circumstances,the staple-firing sled 10050 can be configured to lift the stapledrivers 10040, and the staples 22030 supported thereon, toward the anvil10060. In essence, further to the above, the staple drivers 10040 canmove the staples 22030 from an unfired position (FIG. 407) to a firedposition (FIGS. 408 and 409) wherein the staples 22030 can contact theanvil 10060 and be deformed between an undeformed configuration (FIG.407) and a deformed configuration (FIGS. 408 and 409). As discussedabove, the anvil 10060 can comprise forming pockets 10062 which can beconfigured to receive and deform the staples 22030. Staples 22030 can bethe same as or similar to staples 10030, for example and/or any otherstaples disclosed herein, and, as such, staples 22030 are not describedin greater detail herein. The reader will note, however, that thestaples 22030 can comprise any suitable shape and/or suitabledimensions, such as width and/or height, for example, in theirundeformed configuration and/or their deformed configuration. Forinstance, the staples 22030 can, in certain circumstances, comprise aheight which does not extend above a deck surface 22011 of the cartridgebody 22010 when the staples 22030 are in their unfired positions while,in other circumstances, the staples 22030 can comprise a height in whichthe legs of the staples 22030 extend upwardly from the deck surface22011 when the staples 22030 are in their unfired positions such thatthe legs of the staples 22030 are at least partially embedded in atissue thickness compensator 22010 of the cartridge assembly 22000.

With continued reference to the embodiment depicted in FIGS. 406-409,further to the above, the cartridge assembly 22000 can comprise acartridge body 22010 and a tissue thickness compensator 22020. Invarious circumstances, the cartridge body 22010 can be similar to thesupport portion 10010, for example, in many respects and, as a result,many of such respects are not repeated herein for the sake of brevity.Furthermore, the tissue thickness compensator 22020 can be similar tothe tissue thickness compensator 10020, for example, in many respectsand, as a result, such respects are not repeated herein for the sake ofbrevity. Moreover, the materials and functions of the tissue thicknesscompensators disclosed elsewhere in this application, for example, andthe teachings accompanying the same, are not repeated herein; however,the reader will appreciate that such materials and functions of suchtissue thickness compensators, and the accompanying teachings, areequally applicable to the tissue thickness compensator 22020 wherein, asabove, the details of which are not repeated herein for the sake ofbrevity.

The above being said, with primary reference to FIG. 406, the firingmember 10052 can be advanced distally from the proximal end 22001 towardthe distal end 22002 of the cartridge assembly 22000 to eject thestaples 22030 from the cartridge body 22010. Further to the above, thefiring member 10052 can include a knife portion 10053 which can beconfigured to transect the tissue positioned between the anvil 10060 andthe tissue thickness compensator 22020 as the firing member 10052 isadvanced distally. In various circumstances, as a result, the firingmember 10052 can be configured to concurrently fire the staples 22030 tostaple the tissue T and cut the tissue T. In certain circumstances, thefiring process can at least partially lead the cutting process. Statedanother way, the cutting process can lag the firing process. In suchcircumstances, a portion of the tissue T can be stapled and thenincised. As illustrated in FIGS. 407-409, the cartridge body 22010 caninclude a cartridge knife slot 22015 which can be configured to receivea portion of the firing member 10052 as the firing member 10052 isadvanced distally. In some circumstances, the cartridge knife slot 22015can be configured to receive a portion of the knife portion 10053 of thefiring member 10052. In various circumstances, the cartridge knife slot22015 and the firing member 10052 can be configured such that there areclearance gaps between the sides of the firing member 10052 and the sidewalls of the cartridge knife slot 22015. Alternatively, the cartridgeknife slot 22015 and the firing member 10052 can be configured such thatthe side walls of the cartridge knife slot 20015 can support the firingmember 10052. Further to the above, the anvil 10060 can include an anvilknife slot 10065 which can be configured to receive a portion of thefiring member 10052 as the firing member 10052 is advanced distally. Insome circumstances, the anvil knife slot 10065 can be configured toreceive a portion of the knife portion 10053 of the firing member 10052.In various circumstances, the anvil knife slot 10065 and the firingmember 10052 can be configured such that there are clearance gapsbetween the sides of the firing member 10052 and the side walls of theanvil knife slot 10065. Alternatively, the anvil knife slot 10065 andthe firing member 10052 can be configured such that the side walls ofthe anvil knife slot 10065 can support the firing member 10052.

Referring primarily to FIGS. 407-409, the cartridge knife slot 22015 canbe aligned with the anvil knife slot 10065 such that the cutting member10052 can pass through the cartridge knife slot 22015 and the anvilknife slot 10065 simultaneously. In various circumstances, the anvilknife slot 10065 can extend over the cartridge knife slot 22015 suchthat the knife portion 10053 of the firing member 10052 can pass throughthe cartridge knife slot 22015 and the anvil knife slot 10065simultaneously. The cartridge knife slot 22015 can define a cartridgeknife path for the cutting portion 10053 of the firing member 10052 andthe anvil knife slot 10065 can define an anvil knife path for thecutting portion 10053 wherein the cartridge knife path can be parallelto the anvil knife path. In various circumstances, the cartridge knifepath and the anvil knife path can be longitudinal while, in certaincircumstances, the cartridge knife path and the anvil knife path can becurved. Referring again to FIGS. 406-409, the tissue thicknesscompensator 22020 can comprise a tissue thickness compensator knife slot22025 which can be aligned with the anvil knife slot 10065 and thecartridge knife slot 22015 such that the cutting member 10052 can passthrough the cartridge knife slot 22015, the anvil knife slot 10065, andthe tissue thickness compensator knife slot 22025 simultaneously. Invarious circumstances, the anvil knife slot 10065 can extend over thetissue thickness compensator knife slot 22025 such that the knifeportion 10053 of the firing member 10052 can pass through the cartridgeknife slot 22015, the anvil knife slot 10065, and the tissue thicknesscompensator knife slot 22025 simultaneously. The tissue thicknesscompensator knife slot 22025 can define a tissue thickness compensatorknife path for the cutting portion 10053 wherein the tissue thicknesscompensator knife path can be parallel to the anvil knife path and thecartridge knife path. In various circumstances, the tissue thicknesscompensator knife path can be longitudinal while, in certaincircumstances, the tissue thickness compensator knife path can becurved. Further to the above, curved end effectors and curved fastenercartridges are disclosed in U.S. Patent Application Publication No.2008/0169329. The entire disclosure of U.S. patent application Ser. No.11/652,164, entitled CURVED END EFFECTOR FOR A SURGICAL STAPLING DEVICE,filed on Jan. 11, 2007, now U.S. Patent Application Publication No.2008/0169329, is hereby incorporated by reference herein. In suchembodiments, a tissue thickness compensator can be curved. In at leastone such embodiment, the tissue thickness compensator can be curved tomatch the curvature of the cartridge body of the fastener cartridge.

Further to the above, referring primarily to FIG. 406, the tissuethickness compensator knife slot 22025 can extend between a firststapling portion 22021 a which can be stapled by a first group ofstaples 22030 and a second stapling portion 22021 b which can be stapledby a second group of staples 22030. The knife slot 22025 can releasablyconnect the first stapling portion 22021 a to the second staplingportion 22021 b. In use, as illustrated in FIG. 406, the knife portion10053 can be advanced distally through the knife slot 22025 to transectthe knife slot 22025 and separate the first stapling portion 22021 a andthe second stapling portion 22021 b. In certain circumstances, the knifeslot 22025 can comprise a plurality of connectors, or bridges, 22026which can connect the first stapling portion 22021 a and the secondstapling portion 22021 b prior to being transected by the knife portion10053. In various circumstances, the connectors 22026 can have the samethickness as the first stapling portion 22021 a and/or the secondstapling portion 22021 b, at least when the tissue thickness compensator22020 is in an uncompressed state. In at least one such circumstance,the connectors 22026, the first stapling portion 22021 a, and/or thesecond stapling portion 22021 b can be unitarily and integrally formedfrom a flat, or at least substantially flat, piece of material, forexample. In various other circumstances, the first stapling portion22021 a can comprise a first thickness, the second stapling portion22021 b can comprise a second thickness, and the connectors 22026 cancomprise a third thickness, wherein one or more of the first thickness,the second thickness, and the third thickness can be different than theother thicknesses. The knife slot 22025 can further comprise apertures,such as apertures 22024, for example, defined therein. For instance, theapertures 22024 can be elongate and can extend longitudinally along theknife slot 22025. In various other circumstances, the apertures in theknife slot 22025 can comprise any suitable arrangement. In certaincircumstances, the apertures 22024 can comprise perforations positionedintermediate the connectors 22026 which can be formed utilizing a lasercutting operation, for example. In some circumstances, the apertures22024 can be cut from a sheet of material to form the tissue thicknesscompensator 22020 such that the apertures 22024 and the connectors 22026are arranged in an alternating arrangement, for example. In otherinstances, the tissue thickness compensator 22020 can be molded withapertures 22024 already formed therein. In various circumstances, one ormore of the apertures 22024 can comprise through holes, for example. Invarious circumstances, one or more of the apertures 22024 can compriseclearance apertures, for example. In certain instances, one or more ofthe apertures 22024 may not comprise through holes and may insteadcomprise reductions in the thickness of the knife slot 22025, forexample.

In various circumstances, the apertures 22024 of the tissue thicknesscompensator 22020 could be of varying lengths, such as increasing inlength as they proceed from the proximal end 22001 of the knife slot22025 to the distal end 22002, for example. Alternately, these apertures22024 could decrease in length or vary randomly or in patterns as theyproceed from the proximal end 22001 to the distal end 22002 of the knifeslot 22025. Turning now to FIG. 419, a tissue thickness compensator22320 of a fastener cartridge 22300 can comprise a knife slot 22325extending longitudinally therethrough. The knife slot 22325 can comprisea series of apertures 22324 defined in the tissue thickness compensator22320 which decrease in length when viewed from a proximal end 22321 ofthe tissue thickness compensator 22320 toward a distal end 22322. Forinstance, the first proximal-most aperture 22324 can comprise thelongest aperture 22324, the second proximal-most aperture 22324 cancomprise the second longest aperture 22324, the third proximal-mostaperture 22324 can comprise the third longest aperture 22324, and soforth. In various circumstances, the connectors, or bridges, 22326 inthe knife slot 22325 can be spaced closer to one another at the distalend 22322 of the knife slot 22325 than the proximal end 22321 of theknife slot 22325. As a cutting member is advanced through the knife slot22325, the cutting member may experience an irregular pattern ofresistances which increase in frequency as the cutting member isadvanced distally. In embodiments where a series of apertures 22324defined in the tissue thickness compensator 22320 increase in lengthwhen viewed from the proximal end 22321 of the tissue thicknesscompensator 22320 toward the distal end 22322, the connectors, orbridges, 22326 in the knife slot 22325 can be spaced closer to oneanother at the proximal end 22321 of the knife slot 22325 than thedistal end 22322 of the knife slot 22325. As a cutting member isadvanced through the knife slot 22325 in such circumstances, the cuttingmember may experience an irregular pattern of resistances which decreasein frequency as the cutting member is advanced distally. In variouscircumstances, the connectors 22326 may comprise the same length while,in other circumstances, the connectors 22326 may comprise differentlengths.

Further to the above, referring again to FIGS. 406-408, patient tissuecan be positioned intermediate the anvil 10060 of the end effector 22090and the tissue thickness compensator 22020 of the cartridge assembly22000 when the anvil 10060 is in an open position. When the anvil 10060is moved into a closed position, a bottom surface, or tissue-contactingsurface, 10063 of the anvil 10060 can contact the tissue T and push thetissue T toward a deck surface 22011 of the cartridge body 22010. Thetissue T can contact a top surface, or tissue contacting surface, 22021of the tissue thickness compensator 22020 wherein, when the anvil 10060is moved into its closed position, the anvil 10060 can press the tissueT against the tissue thickness compensator 22020 and, further to theabove, compress the tissue thickness compensator 22020 against the decksurface 22011 of the cartridge body 22010. In various circumstances, thetissue thickness compensator 22020 can comprise a bottom surface 22029which can abut the deck surface 22011. In some circumstances, a gap maybe present between the bottom surface 22029 and the deck surface 22011before the tissue thickness compensator 22020 is compressed against thecartridge body 22010. In such circumstances, the tissue thicknesscompensator 22020 may first translate toward the cartridge body 22010before being compressed thereagainst. When the tissue thicknesscompensator 22020 is compressed against the cartridge body 22010, invarious circumstances, the first stapling portion 22021 a and/or thesecond stapling portion 22021 b of the tissue thickness compensator22020 may move laterally. For instance, the first stapling portion 22021a and/or the second stapling portion 22021 b may move laterally awayfrom the cartridge knife slot 22015. In various circumstances, theconnectors 22026 can be configured to inhibit such lateral movementbetween the first stapling portion 22021 a and the second staplingportion 22021 b. In various circumstances, referring primarily to FIG.408, the connectors 22026 can be configured to stretch to permit somerelative lateral movement between the first stapling portion 22021 a andthe second stapling portion 22021 b when the anvil 10060 is closed. Inthe event that the anvil 10060 is reopened, the connectors 22026 can beconfigured to elastically return, or at least substantially return, totheir unstretched configuration and, as a result, pull the firststapling portion 22021 a and the second stapling portion 22021 blaterally back toward their original positions, illustrated in FIG. 407.Moreover, the anvil 10060 can compress the tissue T when the anvil 10060is moved into its closed position. In such circumstances, the tissue Tmay at least partially flow into the apertures 22024.

Upon reviewing FIGS. 407-409, the reader will appreciate that the knifeslot 22025 of the tissue thickness compensator 22020 comprises lessmaterial along the longitudinal length thereof than the first staplingportion 22021 a and/or the second stapling portion 22021 b. Statedanother way, a longitudinal cross-section through the first staplingportion 22021 a and/or the second stapling portion 22021 b wouldtransect a first amount of material while a longitudinal cross-sectionthrough the knife slot 22025 would transect a second amount of materialwhich is less than the first amount of material.

Once the anvil 10060 has been suitably positioned, further to the above,the firing member 10052 can be advanced distally to fire the staples, asillustrated in FIG. 408, and incise the tissue T and the connectors22026, as illustrated in FIG. 409. In various circumstances, the knifeportion 10053 of the firing member 10052 may experience a firstresistance force when passing through the apertures 22024 and a second,higher, resistance force when incising the connectors 22026. Statedanother way, the force experienced by the knife portion 10053 to incisethe tissue thickness compensator 22020 may alternate between forcepulses experienced when the knife portion 10053 incises the connectors22026 and force dwells experienced when the knife portion 10053 passesthrough the apertures 22024. Further to the above, referring now to FIG.414, the force experienced by the knife portion 10053 to incise thetissue thickness compensator 22020 is depicted by force profile 22200which can include force pulses 22201 and force dwells 22202 whichcorrespond with the knife portion 10053 passing through the connectors22206 and the apertures 22024, respectively. As illustrated in FIG. 414,the force pulses 22201 can comprise a second resistive force F2 appliedto the knife portion 10053 and the force dwells 22202 can comprise afirst resistive force F1 applied to the knife portion 10053, wherein thefirst resistive force F1 can be smaller than the second resistive forceF2. In certain circumstances, the knife portion 10053 may not experiencea force to transect the tissue thickness compensator 22020 when theknife portion 10053 passes through the apertures 22024 and, as a result,the first resistive force F1 can be zero. Such circumstances can arisewhen the apertures 22024 comprise through holes and/or clearance holes,for example. In any event, the width of each force pulse 22201 cancorrespond to the length of the corresponding connector 22026 which gaverise to the force pulse 22201. For instance, the knife portion 10053 canexperience a first force pulse 22201 when moving between distance d0 todistance d1 to transect a first connector 22026, a second force pulse22201 when moving between distance d2 to distance d3 to transect asecond connector 22026, and a third force pulse 22201 when movingbetween distance d4 to distance d5 to transect a third connector 22026,and so forth. Similarly, the width of each force dwell 22202 cancorrespond to the length of the corresponding aperture 22024 which gaverise to the force dwell 22202. For instance, the knife portion 10053 canexperience a first force dwell 22202 when moving between distance d1 todistance d2 through a first aperture 22024 and a second force dwell22201 when moving between distance d3 to distance d4 through a secondaperture 22024, and so forth. While the force pulses 22201 and theconnectors 22026 are depicted as each having the same length, variousembodiments are envisioned in which the force pulses 22201 and theconnectors 22026 can have different lengths. Similarly, while the forcedwells 22202 and the apertures 22024 are depicted as each having thesame length, various embodiments are envisioned in which the forcedwells 22202 and the apertures 22024 can have different lengths.Moreover, other force profiles are envisioned in which a cutting memberexperiences a multitude of pulses which are repeated as part of apattern, repeated without a pattern, and/or not repeated at all. In atleast one circumstance, the cutting member can experience a first pulsehaving a first resistance, a second pulse having a second resistance,and a third pulse having a third resistance, for example.

In various circumstances, turning now to FIG. 415, a force pulse 22201can represent a constant, or at least nearly constant, second resistiveforce F2 which is applied to the knife portion 10053 during the durationof the force pulse 22201. Such a constant force is depicted by a flatpeak 22203, for example, which is illustrated with phantom lines. Inother circumstances, a force pulse 22201 can represent a secondresistive force F2 which varies during the duration of the force pulse22201. For instance, such a varied resistive force F2 can be representedby a non-flat peak 22204, for example. In at least one circumstance, thenon-flat peak 22204 can comprise a high force point 22205 and a lowforce point 22206. In some circumstances, the high force point 22205 canbe present at the beginning of the force pulse 22201, for example. Insome circumstances, the low force point 22206 can be present at the endof the force pulse 22201, for example.

As discussed above, with reference to FIG. 415, the knife portion 10053can experience a force to transect the tissue thickness compensator22020, for example. In various circumstances, the knife portion 10053can experience other forces such as, one, a force experienced totransect the patient tissue T (FIG. 416), two, a drag force experiencedwhen the knife portion 10053 slides through the transected portions ofthe tissue thickness compensator 22020 (FIG. 417), and/or, three, a dragforce experienced when the knife portion 10053 slides through thetransected portion of the tissue T (FIG. 418). Referring to FIG. 416,the force experienced by the knife portion 10053 to transect the patienttissue T, i.e., the tissue incision force, can be represented by forceprofile 22210. In certain circumstances, the tissue incision force canbe constant as the knife portion 10053 is advanced distally through itsfiring stroke, as represented by force profile 22210 a. The reader willappreciate, however, that patient tissue is rarely homogeneous and, assuch, the patient tissue will comprise thicker and/or tougher sectionsas well as thinner and/or softer sections. In such circumstances, thetissue incision force experienced by the knife portion 10053 may changeduring the firing stroke of the firing member 10052. Moreover, thetissue incision force experienced by the knife portion 10053 maydecrease during the firing stroke of the firing member 10052, asrepresented by force profile 22210 b. Such circumstances may arise whenfluids from the transected tissue T accumulate on the knife portion10053 which can lubricate the knife portion 10053 as the knife portionis advanced distally. Moreover, the tissue incision force experienced bythe knife portion 10053 may increase during the firing stroke of thefiring member 10052, as represented by force profile 22210 c. Suchcircumstances may arise when the tissue T is being at least partiallypushed, or plowed, distally by the knife portion 10053 in lieu of beingtransected by the knife portion 10053, for example.

Referring now to FIG. 417, the drag force experienced by the knifeportion 10053 as it passes through the tissue thickness compensator22020 can be represented by force profile 22220. In variouscircumstances, the transected portions of the tissue thicknesscompensator 22020 can wipe against the sides of the knife portion 10053,for example, as the knife portion 10053 passes through the tissuethickness compensator 22020. Such wiping action can apply a drag forceto the knife portion 10053 which can increase as the knife portion 10053moves distally through the tissue thickness compensator 22020. Withreference to force profile 22220 depicted in FIG. 417, the drag forcecan increase during ramp periods 22221 in which the knife portion 10053is passing through a newly transected connector 22026, for example. Incertain circumstances, the drag force can remain constant, or at leastsubstantially constant, during dwell periods 22222 as the knife portion10053 passes through a new aperture 22024, especially when the aperture22024 comprises a clearance slot, for example. In embodiments whereinthe aperture 22024 comprises a reduction in the thickness of the knifeslot 22025, the drag force experienced by the knife portion 10053 as itpasses through the tissue thickness compensator 22020 can increaseduring periods 22222, for example. Referring now to FIG. 418, the dragforce experienced by the knife portion 10053 as it passes through thetissue T can be represented by force profile 22230. In variouscircumstances, the transected portions of the tissue T can wipe againstthe sides of the knife portion 10053, for example, as the knife portion10053 passes through the tissue T. Such wiping action can apply a dragforce to the knife portion 10053 which can increase as the knife portion10053 moves distally through the tissue T. With reference to forceprofile 22230 depicted in FIG. 418, such a drag force can increase, forexample, as the knife portion 10053 is advanced distally.

Further to the above, the tissue thickness compensator incision force,the tissue incision force, the tissue thickness compensator drag force,and/or the tissue drag force can dull the knife portion 10053 of thefiring member 10052. A dull knife may not be able to transect the tissueT and/or the tissue thickness compensator 22020, for example, accordingto a preferred manner. With primary reference to FIG. 409, the knifeportion 10053 can comprise a first knife edge zone 10053 a, a secondknife edge zone 10053 b, and/or a third knife edge zone 10053 c, forexample, wherein the first knife edge zone 10053 a is positionedvertically above the second knife edge zone 10053 b, and wherein thesecond knife edge zone 10053 b is positioned vertically above the thirdknife edge zone 10053 c, for example. The knife portion 10053 cancomprise any suitable number and/or location of knife edge zones whereinthe knife edge zones depicted in FIG. 409 have been selected for thepurposes of discussion. Further to the above, the first knife edge zone10053 a can be configured to transect the tissue T while the secondknife edge zone 10053 b can be configured to transect the tissuethickness compensator 22020. As a result, the first knife edge zone10053 a may experience the tissue incision force and/or the tissue dragforce discussed above. Such forces may wear or dull the first knife edgezone 10053 a at a first rate. The second knife edge zone 10053 b mayexperience the tissue thickness compensator incision force and/or thetissue thickness compensator drag force discussed above. Such forces maywear or dull the second knife edge zone 10053 b at a second rate. Invarious circumstances, the second rate can be different than the firstrate. In certain circumstances, the sum of the tissue thicknesscompensator incision force and the tissue thickness compensator dragforce can be larger than the sum of the tissue incision force and thetissue drag force and, as a result, the second rate can be faster thanthe first rate. In some circumstances, the tissue thickness compensatordrag force and/or the tissue drag force can be negligible. In at leastsome such circumstances, the tissue thickness compensator incision forcecan be larger than the tissue incision force and, as a result, thesecond rate can be faster than the first rate. Other embodiments areenvisioned in which the first rate is faster than the second rate.

As discussed above, the second knife edge zone 10053 b of the cuttingmember 10053 may wear or dull at a faster rate than the first knife edgezone 10053 a, especially after several uses of the surgical instrumentand/or the end effector 22090. In such circumstances, the knife member10053 may reach a condition in which the first knife edge zone 10053 ais suitably sharp to transect the tissue T while the second knife edgezone 10053 b may not be sufficiently sharp to transect a tissuethickness compensator 22020 as desired. When the second knife edge zone10053 b is dull, for instance, the knife portion 10053 may push or plowthe tissue thickness compensator 22020 distally before incising it, forexample. In such circumstances, the knife portion 10053 may at leastpartially displace or dislodge the tissue thickness compensator 22020.In view of the above, the tissue thickness compensator 22020 can bedesigned such that the second wear rate of the second knife edge zone10053 b is equal to the first wear rate of the first knife edge zone10053 a wherein, as a result, the first knife edge zone 10053 a and thesecond knife edge zone 10053 b can wear at the same rate. In somecircumstances, owing to certain predictable and/or unpredictablevariables, it may not be possible to balance the first wear rate withthe second wear rate; however, the tissue thickness compensator 22020can be configured such that the first wear rate is sufficiently balancedwith the second wear rate. In at least some such circumstances, thetissue thickness compensator 22020 can be designed such the second knifeedge zone 10053 b remains sufficiently sharp during a predeterminednumber or uses of the surgical instrument and/or the end effector 22090.For instance, the height and the length of the connectors 22026 in theknife slot 22025 can be selected such that the second wear rate issufficiently low enough for the knife portion 10053 of the firing member10052 to remain sufficiently sharp to fire at least twelve fastenercartridges 22000, for example. At the end of the predetermined number ofuses, the first knife edge zone 10053 a will have remained sufficientlysharp enough to transect the tissue T and the second knife edge zone10053 b will have remained sufficiently sharp enough to transect thetissue thickness compensators 22020 of the fastener cartridges 22000. Invarious circumstances, further to the above, the third knife edge zone10053 c may not transect the tissue T and/or the tissue thicknesscompensator 22020, for example, and may not wear, or substantially wear,during use.

In various circumstances, further to the above, the size andconfiguration of the connectors 22026 and the apertures 22024 of theknife slot 22025 can be selected such that the tissue thicknesscompensator incision force and/or the tissue thickness compensator dragforce are lower such that the cumulative force acting on the secondknife edge zone 10053 b is lower, or closer to, the cumulative forceacting on the first knife edge zone 10053 a. In certain circumstances,the configuration of the connectors 22026 can be selected such that theconnectors 22026 are more easily incised by the knife portion 10053.Similarly, in certain circumstances, the configuration of the connectors22026 can be selected such that they apply less drag to the knifeportion 10053 after they have been incised.

Turning now to FIGS. 420 and 421, a fastener cartridge 22400 cancomprise a tissue thickness compensator 22420 which can include a firststapling portion 22421 a and a second stapling portion 22421 b which areconnected by a knife slot 22425. The knife slot 22425 can comprise anangled longitudinal connector 22426. The angled longitudinal connector22426 can extend between a proximal end 22401 of the knife slot 22425and a distal end 22402 of the knife slot 22425. In some circumstances,the angled longitudinal connector 22426 can extend the entire length ofthe knife slot 22425 while, in other circumstances, the angledlongitudinal connector 22426 can extend less than the length of theknife slot 22425. The angled longitudinal connector 22426 can extendbetween a top surface 22428 of the tissue thickness compensator 22420and a bottom surface 22429 of the tissue thickness compensator 22420. Insome circumstances, the angled longitudinal connector 22426 can extendthe entire distance between the top surface 22428 and the bottom surface22429 while, in other circumstances, the angled longitudinal connector22426 can extend less than the distance between the top surface 22428and the bottom surface 22429. In various circumstances, the proximal endof the longitudinal connector 22426 can extend from the top surface22428 of the tissue thickness compensator while the distal end of thelongitudinal connector 22426 can extend from the bottom surface 22429.Alternatively, the distal end of the longitudinal connector 22426 canextend from the top surface 22428 of the tissue thickness compensatorwhile the proximal end of the longitudinal connector 22426 can extendfrom the bottom surface 22429. In various embodiments, the longitudinalconnector 22426 can comprise a thin bridge (i.e. less than the fullthickness of the tissue thickness compensator 22420) or a series of thinbridges that join the first stapling portion 22421 a which can bestapled by a first group of staples 22030 to the second stapling portion22421 b which can be stapled by a second group of staples 22030, forexample. These thin, angled bridges, and/or the longitudinal connector22426, could distribute the wear across the second knife edge zone 10053b, rather than concentrating it on one spot. In various circumstances,as a result, the wear occurring on the second knife edge zone 10053 bmay be equal to, or closer to being equal to, the wear occurring at thefirst knife edge zone 10053 a, for example.

As discussed above, a fastener cartridge can include a gap settingelement 10059 which can be configured to limit the travel of an anvil,such as anvil 10060, for example. Turning now to FIGS. 410-413, an endeffector of a surgical fastening instrument, such as end effector 22190,for example, can comprise a first jaw including a fastener cartridgeassembly 22100 and a second jaw including an anvil 10060. The first jawcan include a staple cartridge channel 10070 which can be configured toremovably receive the cartridge assembly 22100. Alternatively, thestaple cartridge channel 10070 and the cartridge assembly 22100 cancomprise an integral unit. In various circumstances, the anvil 10060 canbe moved between an open position (FIG. 410) and a closed position (FIG.411). In the open position of the anvil 10060, the anvil 10060 can bepositioned on a first side of a patient's tissue T and the cartridgeassembly 22100 can be positioned on a second, or opposite, side of thetissue T, for example. When the anvil 10060 is moved into its closedposition, the anvil 10060 can compress the tissue T against thecartridge assembly 22100. Alternatively, with reference to FIG. 395,discussed above, the first jaw including the cartridge assembly 22100can be moved relative to the anvil 10060. In either event, the endeffector 22190 can be closed by a closure drive of a surgical fasteninginstrument, as discussed above. Alternatively, the end effector 22190can be closed by a firing member, such as firing member 10052, forexample, when the firing member 10052 is advanced distally from aproximal end 22101 (FIG. 412) of the cartridge assembly 22100 toward adistal end 22102 (FIG. 412) of the cartridge assembly 22100. Whether ornot the firing member 10052 is utilized to close the end effector 22190,the firing member 10052 can be configured to eject fasteners, such asstaples 22130, for example, removably stored in a cartridge body 22110of the cartridge assembly 22100 as the cutting member 10052 is advancedfrom the proximal end 22101 toward the distal end 22102 of the cartridgeassembly 22100.

Further to the above, the staples 22130 can be supported by stapledrivers 10040 which are movably positioned within staple cavities 22112defined in the cartridge body 22110. Moreover, the firing member 10052can be configured to advance a staple-firing sled 10050 distally as thefiring member 10052 is moved from the proximal end 22101 toward thedistal end 22102 wherein the staple-firing sled 10050 can be configuredto lift the staple drivers 10040, and the staples 22130 supportedthereon, toward the anvil 10060. In essence, further to the above, thestaple drivers 10040 can move the staples 22130 from an unfired positionto a fired position wherein the staples 22130 can contact the anvil10060 and can be deformed between an undeformed configuration and adeformed configuration. As discussed above, the anvil 10060 can compriseforming pockets 10062 which can be configured to receive and deform thestaples 22130. Staples 22130 can be the same as or similar to staples10030, for example, and/or any other staples disclosed herein, and, assuch, staples 22130 are not described in greater detail herein. Thereader will note, however, that the staples 22130 can comprise anysuitable shape and/or suitable dimensions, such as width and/or height,for example, in their undeformed configuration and/or their deformedconfiguration. For instance, the staples 22130 can, in certaincircumstances, comprise a height which does not extend above a decksurface 22111 of the cartridge body 22110 when the staples 22130 are intheir unfired positions while, in other circumstances, the staples 22130can comprise a height in which the legs of the staples 22130 extendupwardly from the deck surface 22111 when the staples 22130 are in theirunfired positions such that the legs of the staples 22130 are at leastpartially embedded in a tissue thickness compensator 22110 of thecartridge assembly 22100, as illustrated in FIG. 410.

With continued reference to the embodiment depicted in FIGS. 410-413,further to the above, the cartridge assembly 22100 can comprise acartridge body 22110 and a tissue thickness compensator 22120. Invarious circumstances, the cartridge body 22110 can be similar to thesupport portion 10010 and/or the cartridge body 22010, for example, inmany respects and, as a result, many of such respects are not repeatedherein for the sake of brevity. Furthermore, the tissue thicknesscompensator 22120 can be similar to the tissue thickness compensator10020 and/or the tissue thickness compensator 22020, for example, inmany respects and, as a result, such respects are not repeated hereinfor the sake of brevity. Moreover, the materials and functions of thetissue thickness compensators disclosed elsewhere in this application,for example, and the teachings accompanying the same, are not repeatedherein; however, the reader will appreciate that such materials andfunctions of such tissue thickness compensators, and the accompanyingteachings, are equally applicable to the tissue thickness compensator22120 wherein, as above, the details of which are not repeated hereinfor the sake of brevity.

Referring again to FIGS. 410-413, the cartridge body 22110 can compriseone or more gap setting elements, such as a first gap setting element22159 a and a second gap setting element 22159 b, for example, extendingtherefrom. While two gap setting elements are disclosed in theembodiment of FIGS. 410-413, any suitable number of gap elements can beutilized, such as one gap element, for example, or three or more gapelements, for example. In various circumstances, the gap settingelements 22159 a and 22159 b can extend from the distal end 22102 of thecartridge body 22110. In certain circumstances, the gap setting elements22159 a and 22159 b can extend from a distal nose 22103 of the cartridgebody 22110. The gap setting element 22159 a and/or the gap settingelement 22159 b can be integrally formed with the cartridge body 22110.For instance, the cartridge body 22110 and the gap setting elements22159 a and 22159 b can be integrally formed during an injection moldingprocess, for example. In such circumstances, the cartridge body 22110and the gap setting elements 22159 a and 22159 b can be comprised of thesame material. In certain circumstances, the gap setting element 22159 aand/or the gap setting element 22159 b can be assembled to the cartridgebody 22110. For instance, the cartridge body 22110 can be formed withapertures defined therein which can be configured to receive the gapsetting elements 22159 a and 22159 b. In such circumstances, thecartridge body 22110 and the gap setting elements 22159 a and 22159 bcan be comprised of the same material and/or different materials. In atleast one such circumstance, the cartridge body 22110 can be comprisedof a first plastic material and the gap setting elements 22159 a and22159 b can be comprised of a second plastic material, for example. Insome circumstances, the cartridge body 22110 can be comprised of aplastic material and the gap setting elements 22159 a and 22159 b can becomprised of a metal material, for example. In various circumstances,the first gap setting element 22159 a can be positioned laterally in afirst direction with respect to a knife slot defined in the cartridgebody 22110 and the second gap setting element 22159 b can be positionedlaterally in a second direction with respect to the cartridge knifeslot. Stated another way, the first gap setting element 22159 a can bepositioned on a first side of the cartridge knife slot and the secondgap setting element 22159 b can be positioned on a second side of thecartridge knife slot. Moreover, the first gap setting element 22159 acan be positioned on a first side of a knife slot 22025 defined in thetissue thickness compensator 22120 and the second gap setting element22159 b can be positioned on a second side of the knife slot 22025. Insuch circumstances, the knife slot 22025 can extend between the firstgap setting element 22159 a and the second gap setting element 22159 b.

Referring again to FIGS. 410 and 411, the anvil 10060 can be movedbetween an open position (FIG. 410) and a closed position (FIG. 411) tocompress the tissue T against the tissue thickness compensator 22120 andcompress the tissue thickness compensator 22120 against the cartridgebody 22110. More specifically, the bottom surface 10063 of the anvil10060 can be positioned against the tissue T to push the tissue Tdownwardly against a top surface 22121 of the tissue thicknesscompensator 22120. The anvil 10060 can push the tissue thicknesscompensator 22120 downwardly such that a bottom surface 22129 of thetissue thickness compensator 22120 contacts the deck surface 22111 ofthe cartridge body 22110. In various circumstances, the anvil 10060 canbe moved toward the cartridge body 22110 in order to compress the tissueT and the tissue thickness compensator 22120 therebetween wherein a gap22199 (FIG. 411) can be present between the bottom surface 10063 of theanvil 10060 and the cartridge deck 22111. In certain circumstances, thegap 22199 can be maintained within a certain range of distances suchthat the anvil pockets 10062 of the anvil 10060 are positioned at adesired distance, or within a range of desired distances, from thecartridge body 22110 and that the staples 22130 are deformed to adesired height, or within a range of desired heights, when the staples22130 are ejected from the cartridge body 22110.

Further to the above, the end effector 22190 can be utilized to stapleand incise patient tissue in a multitude of circumstances. For instance,when a vessel is positioned intermediate the anvil 10060 and the tissuethickness compensator 22120, for example, patient tissue may not extendover the nose 22103 of the cartridge body 22110. In some circumstances,the vessel can be positioned between the proximal end of the tissuethickness compensator 22120 and the distal end of the tissue thicknesscompensator 22120. When a thick vessel is present between the anvil10060 and the tissue thickness compensator 22120, for example, the anvil10060 may reach a final, or closed, position in which the anvil 10060 isnot in contact with the gap setting elements 22159 a and 22159 b. Insuch circumstances, the gap 22199 can be maintained without theassistance of the gap setting elements 22159 a and 22159 b. Forinstance, in embodiments where the firing member 10052 has one or morecams extending therefrom, the firing member 10052 can engage andposition the anvil 10060 in order to control the gap 22199. Moreparticularly, referring primarily to FIG. 413, the firing member 10052can comprise an upper pair of cams 10049 extending laterally therefromwhich can be configured to engage one or more cam ledges 10097 definedon the anvil 10060 and a lower pair of cams 10054 extending laterallytherefrom which can be configured to engage the cartridge body 22110. Asthe firing member 10052 is advanced distally, the upper cams 10049 andthe lower cams 10054 can co-operate to position the anvil 10060 relativeto the cartridge body 22110 and set the gap 22199. In embodiments wherethe firing member 10052 may not comprise cam members configured to movethe anvil 10060 and set the gap 22199, a closure tube of the surgicalinstrument, for example, can pivot the anvil 10060 into position.

In various circumstances, further to the above, the anvil 10060 can abutthe gap setting elements 22159 a and 22159 b when a thin vessel ispresent between the anvil 10060 and the tissue thickness compensator22120, for example. In such circumstances, the gap setting elements22159 a and 22159 b can arrest the movement of the anvil 10060. Ineffect, the gap setting elements 22159 a and 22159 b can set the minimumgap between the anvil 10060 and the cartridge deck 22111. This minimumgap is depicted in FIG. 411. In various circumstances, the gap settingelements 22159 a and 22159 b can be rigid and may not deflect, or atleast substantially deflect, under the compressive load applied theretoby the anvil 10060. In various circumstances, further to the above, theend effector 22190 can be utilized to staple and incise tissue T whereinat least a portion of the tissue T extends out over the distal nose22103 of the cartridge body 22110. In some circumstances, as a result, aportion of the tissue T can extend over the gap setting elements 22159 aand 22159 b and, eventhough the anvil 10060 may be moved into a final,or closed, position to set the gap 22199, the anvil 10060 may notdirectly contact the gap setting elements 22159 a and 22159 b. In somecircumstances, referring to FIG. 413, the tissue extending over the gapsetting elements 22159 a and 22159 b may be very thin and notsubstantially affect the position of the anvil 11060. Nonetheless, thegap setting elements 22159 a and 22159 b may still limit the travel ofthe anvil 10060 and can, as a result, set the gap 22199 eventhough thereis tissue positioned between the anvil 10060 and the gap settingelements 21259 a and 22159 b.

The above being said, with primary reference to FIG. 413, the firingmember 10052 can be advanced distally from the proximal end 22101 towardthe distal end 22102 of the cartridge assembly 22100 to eject thestaples 22130 from the cartridge body 22110. Further to the above, thefiring member 10052 can include a knife portion 10053 which can beconfigured to transect the tissue positioned between the anvil 10060 andthe tissue thickness compensator 22120 as the firing member 10052 isadvanced distally. In various circumstances, as a result, the firingmember 10052 can be configured to concurrently fire the staples 22130 tostaple the tissue T and cut the tissue T. In certain circumstances, thefiring process can at least partially lead the cutting process. Statedanother way, the cutting process can lag the firing process. In suchcircumstances, a portion of the tissue T can be stapled and thenincised.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

Preferably, the invention described herein will be processed beforesurgery. First, a new or used instrument is obtained and if necessarycleaned. The instrument can then be sterilized. In one sterilizationtechnique, the instrument is placed in a closed and sealed container,such as a plastic or TYVEK bag. The container and instrument are thenplaced in a field of radiation that can penetrate the container, such asgamma radiation, x-rays, or high-energy electrons. The radiation killsbacteria on the instrument and in the container. The sterilizedinstrument can then be stored in the sterile container. The sealedcontainer keeps the instrument sterile until it is opened in the medicalfacility.

Various embodiments described herein are described in the context ofstaples removably stored within staple cartridges for use with surgicalstapling instruments. In some circumstances, staples can include wireswhich are deformed when they contact an anvil of the surgical stapler.Such wires can be comprised of metal, such as stainless steel, forexample, and/or any other suitable material. Such embodiments, and theteachings thereof, can be applied to embodiments which include fastenersremovably stored with fastener cartridges for use with any suitablefastening instrument.

Various embodiments described herein are described in the context oftissue thickness compensators attached to, and/or for use with, staplecartridges and/or fastener cartridges. Such tissue thicknesscompensators can be utilized to compensate for variations in tissuethickness from one end of a staple cartridge to another, or forvariations in tissue thickness captured within one staple, or fastener,as compared to another. Such tissue thickness compensators can also beutilized to compensate for variations in tissue thickness from one sideof a staple cartridge to another. Such embodiments, and the teachingsthereof, can be applied to embodiments which include a layer, or layers,of material attached to, and/or for use with, staple cartridges and/orfastener cartridges. A layer can include buttress material.

Various embodiments described herein are described in the context oflinear end effectors and/or linear fastener cartridges. Suchembodiments, and the teachings thereof, can be applied to non-linear endeffectors and/or non-linear fastener cartridges, such as, for example,circular and/or contoured end effectors. For example, various endeffectors, including non-linear end effectors, are disclosed in U.S.patent application Ser. No. 13/036,647, filed Feb. 28, 2011, entitledSURGICAL STAPLING INSTRUMENT, now U.S. Patent Application PublicationNo. 2011/0226837, which is hereby incorporated by reference in itsentirety. Additionally, U.S. patent application Ser. No. 12/893,461,filed Sep. 29, 2012, entitled STAPLE CARTRIDGE, now U.S. PatentApplication Publication No. 2012/0074198, is hereby incorporated byreference in its entirety. U.S. patent application Ser. No. 12/031,873,filed Feb. 15, 2008, entitled END EFFECTORS FOR A SURGICAL CUTTING ANDSTAPLING INSTRUMENT, now U.S. Pat. No. 7,980,443, is also herebyincorporated by reference in its entirety.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

What is claimed is:
 1. A fastener cartridge assembly, comprising: acartridge body comprising a fastener cavity; a tissue thicknesscompensator releasably secured relative to said cartridge body, whereinsaid tissue thickness compensator comprises: a first aperture extendingalong a first predefined trajectory; and a second aperture extendingalong a second predefined trajectory; and a fastener removablypositioned in said fastener cavity, wherein said fastener comprises: afirst leg aligned with said first aperture and moveable along said firstpredefined trajectory; and a second leg aligned with said secondaperture and moveable along said second predefined trajectory.
 2. Thefastener cartridge assembly of claim 1, wherein said first predefinedtrajectory is parallel to said second predefined trajectory.
 3. Thefastener cartridge assembly of claim 2, wherein said fastener ismoveable along a fastener axis, and wherein said first leg and saidsecond leg are parallel to said fastener axis.
 4. The fastener cartridgeassembly of claim 1, wherein a clearance is defined between said firstleg and said first aperture when said first leg moves along said firstpredefined trajectory.
 5. The fastener cartridge assembly of claim 1,wherein said second aperture is wider than said second leg.
 6. Thefastener cartridge assembly of claim 1, wherein said first aperture andsaid second aperture extend at least partially through said tissuethickness compensator.
 7. A fastener cartridge assembly, comprising: acartridge body comprising a fastener cavity; a fastener comprising afirst leg and a second leg, wherein said fastener is moveable from anunfired configuration to a fired configuration; and a tissue thicknesscompensator releasably secured relative to said cartridge body, whereinsaid tissue thickness compensator comprises: a first clearance pathdefined at least partially through said tissue thickness compensator;and a second clearance path defined at least partially through saidtissue thickness compensator, wherein said first leg moves along saidfirst clearance path and said second leg moves along said secondclearance path when said fastener moves from the unfired configurationto the fired configuration.
 8. The fastener cartridge assembly of claim7, wherein said first clearance path is parallel to said secondclearance path.
 9. The fastener cartridge assembly of claim 7, whereinsaid first clearance path is longer than said first leg.
 10. Thefastener cartridge assembly of claim 7, wherein a gap is defined betweensaid second leg and said tissue thickness compensator when said secondleg moves along said second clearance path.
 11. A fastener cartridgeassembly, comprising: a cartridge body comprising a fastener cavity; afastener comprising a fastener leg, wherein said fastener leg defines aleg length; and a tissue thickness compensator releasably securedrelative to said cartridge body, wherein said tissue thicknesscompensator comprises a predefined opening that is aligned with saidfastener leg, and wherein said predefined opening defines an openinglength that is greater than said leg length.
 12. The fastener cartridgeassembly of claim 11, wherein said fastener moves along a fastener axisbetween an unfired configuration and a fired configuration, and whereinsaid predefined opening extends along an axis that is parallel to saidfastener axis.
 13. The fastener cartridge assembly of claim 11, whereinsaid fastener leg defines a leg width, and wherein said predefinedopening further comprises an opening width that is greater than said legwidth.
 14. The fastener cartridge assembly of claim 11, wherein saidpredefined opening further comprises an opening trajectory, and whereinsaid fastener leg further comprises a leg trajectory that matches saidopening trajectory.
 15. A fastener cartridge assembly, comprising: acartridge body comprising a fastener cavity; a fastener comprising afastener leg, wherein said fastener leg defines a leg diameter; and atissue thickness compensator releasably secured relative to saidcartridge body, wherein said tissue thickness compensator comprises apredefined opening that is aligned with said fastener leg, and whereinsaid predefined opening defines an opening diameter that is greater thansaid leg diameter.
 16. The fastener cartridge assembly of claim 15,wherein said cartridge body comprises a deck, and wherein saidpredefined opening extends into said cartridge body along an axis thatis perpendicular to said deck.
 17. The fastener cartridge assembly ofclaim 15, wherein said fastener leg defines a leg length, and whereinsaid predefined opening further comprises an opening length that isgreater than said leg length.
 18. The fastener cartridge assembly ofclaim 15, wherein said predefined opening further comprises an openingtrajectory, and wherein said fastener leg further comprises a legtrajectory that matches said opening trajectory.
 19. A fastenercartridge assembly, comprising: a cartridge body comprising a pluralityof fastener cavities; a plurality of fasteners, wherein said fastenersare moveable from a unfired configuration to a fired configuration; anda tissue thickness compensator releasably secured relative to saidcartridge body, wherein said fasteners move at least partially throughsaid tissue thickness compensator when said fasteners are moved from theunfired configuration to the fired configuration, and wherein saidtissue thickness compensator comprises clearance means for reducingfriction between said fasteners and said tissue thickness compensator.20. The fastener cartridge assembly of claim 19, wherein each saidfastener further comprises a staple leg that is at least partiallyembedded in said tissue thickness compensator when said fastener is inthe unfired configuration.
 21. A fastener cartridge assembly forfastening patient tissue, the fastener cartridge assembly comprising: acartridge body comprising a plurality of fastener cavities; a pluralityof fasteners, wherein said fasteners are moveable from a unfiredconfiguration to a fired configuration; a tissue thickness compensator,wherein said fasteners are configured to capture a portion of thepatient tissue and a portion of the tissue thickness compensator whensaid fasteners are moved between the unfired configuration and the firedconfiguration; and expansion means for reforming the tissue thicknesscompensator to consume the space within the fasteners not consumed bythe patient tissue.